39 changed files with 620 additions and 954 deletions
--- a/.envrc
+++ b/.envrc
@ -1,3 +0,0 @@
-#!/usr/bin/env bash
-
-use flake
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@ -0,0 +1,64 @@
+on: [push, pull_request]
+
+name: Continuous Integration
+
+jobs:
+  check:
+    name: Check
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+      - uses: actions-rs/cargo@v1
+        with:
+          command: check
+
+  test:
+    name: Test Suite
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+      - uses: actions-rs/cargo@v1
+        with:
+          command: test
+
+  fmt:
+    name: Rustfmt
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+      - run: rustup component add rustfmt
+      - uses: actions-rs/cargo@v1
+        with:
+          command: fmt
+          args: --all -- --check
+
+  clippy:
+    name: Clippy
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+      - run: rustup component add clippy
+      - uses: actions-rs/cargo@v1
+        with:
+          command: clippy
+          args: -- -D warnings
--- a/.gitignore
+++ b/.gitignore
@ -1,4 +1,5 @@
-.direnv/
-coverage/
-debug/
+# Compiled files and executables.
 target/
+
+# Backup files generated by rustfmt.
+**/*.rs.bk
--- a/Cargo.lock
+++ b/Cargo.lock
@ -1,63 +1,29 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
-
 [[package]]
-name = "anstream"
-version = "0.6.11"
+name = "aho-corasick"
+version = "0.7.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6e2e1ebcb11de5c03c67de28a7df593d32191b44939c482e97702baaaa6ab6a5"
+checksum = "043164d8ba5c4c3035fec9bbee8647c0261d788f3474306f93bb65901cae0e86"
 dependencies = [
- "anstyle",
- "anstyle-parse",
- "anstyle-query",
- "anstyle-wincon",
- "colorchoice",
- "utf8parse",
+ "memchr",
 ]

 [[package]]
-name = "anstyle"
-version = "1.0.4"
+name = "ansi_term"
+version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7079075b41f533b8c61d2a4d073c4676e1f8b249ff94a393b0595db304e0dd87"
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-checksum = "c75ac65da39e5fe5ab759307499ddad880d724eed2f6ce5b5e8a26f4f387928c"
+checksum = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 dependencies = [
- "utf8parse",
-]
-
-[[package]]
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-dependencies = [
- "anstyle",
- "windows-sys",
+ "winapi",
 ]

 [[package]]
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-version = "2.0.13"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "00ad3f3a942eee60335ab4342358c161ee296829e0d16ff42fc1d6cb07815467"
+checksum = "c88b9ca26f9c16ec830350d309397e74ee9abdfd8eb1f71cb6ecc71a3fc818da"
 dependencies = [
- "anstyle",
- "bstr",
 "doc-comment",
 "predicates",
 "predicates-core",
@ -66,91 +32,42 @@ dependencies = [
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 [[package]]
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-version = "1.3.2"
+name = "atty"
+version = "0.2.14"
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-checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
-
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-checksum = "c48f0051a4b4c5e0b6d365cd04af53aeaa209e3cc15ec2cdb69e73cc87fbd0dc"
+checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
 dependencies = [
- "memchr",
- "regex-automata",
- "serde",
+ "hermit-abi",
+ "libc",
+ "winapi",
 ]

 [[package]]
-name = "cfg-if"
-version = "1.0.0"
+name = "bitflags"
+version = "1.2.1"
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-checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
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 [[package]]
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+version = "2.33.3"
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-checksum = "1e578d6ec4194633722ccf9544794b71b1385c3c027efe0c55db226fc880865c"
+checksum = "37e58ac78573c40708d45522f0d80fa2f01cc4f9b4e2bf749807255454312002"
 dependencies = [
- "clap_builder",
- "clap_derive",
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-dependencies = [
- "anstream",
- "anstyle",
- "clap_lex",
+ "ansi_term",
+ "atty",
+ "bitflags",
 "strsim",
+ "textwrap",
+ "unicode-width",
+ "vec_map",
 ]

 [[package]]
-name = "clap_derive"
-version = "4.4.7"
+name = "difference"
+version = "2.0.0"
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-
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-
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-checksum = "6184e33543162437515c2e2b48714794e37845ec9851711914eec9d308f6ebe8"
+checksum = "524cbf6897b527295dff137cec09ecf3a05f4fddffd7dfcd1585403449e74198"

 [[package]]
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@ -159,66 +76,25 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
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 [[package]]
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+name = "hermit-abi"
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+checksum = "3deed196b6e7f9e44a2ae8d94225d80302d81208b1bb673fd21fe634645c85a9"
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- "hard-xml-derive",
- "jetscii",
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-
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-dependencies = [
- "console",
- "lazy_static",
- "linked-hash-map",
- "similar",
- "yaml-rust",
+ "libc",
 ]

 [[package]]
 name = "itoa"
-version = "1.0.10"
+version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b1a46d1a171d865aa5f83f92695765caa047a9b4cbae2cbf37dbd613a793fd4c"
+checksum = "dc6f3ad7b9d11a0c00842ff8de1b60ee58661048eb8049ed33c73594f359d7e6"

 [[package]]
 name = "jetscii"
-version = "0.5.3"
+version = "0.4.4"
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-checksum = "47f142fe24a9c9944451e8349de0a56af5f3e7226dc46f3ed4d4ecc0b85af75e"
+checksum = "5f25cca2463cb19dbb1061eb3bd38a8b5e4ce1cc5a5a9fc0e02de486d92b9b05"

 [[package]]
 name = "lazy_static"
@ -228,126 +104,130 @@ checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"

 [[package]]
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 [[package]]
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 [[package]]
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+version = "1.1.1"
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- "hard-xml",
+ "regex",
 "serde",
+ "strong-xml",
 "thiserror",
 ]

 [[package]]
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-version = "1.1.6"
+version = "1.1.1"
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 "clap",
- "insta",
 "opml",
 "serde",
 "serde_json",
- "test-case",
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 dependencies = [
- "anstyle",
- "difflib",
+ "difference",
 "predicates-core",
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+version = "1.0.0"
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- "termtree",
+ "treeline",
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-version = "3.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "adcb7fd841cd518e279be3d5a3eb0636409487998a4aff22f3de87b81e88384f"
-dependencies = [
- "cfg-if",
- "proc-macro2",
- "quote",
- "syn 2.0.48",
-]
-
-[[package]]
-name = "test-case-macros"
-version = "3.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c89e72a01ed4c579669add59014b9a524d609c0c88c6a585ce37485879f6ffb"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.48",
- "test-case-core",
+ "unicode-width",
 ]

 [[package]]
 name = "thiserror"
-version = "1.0.56"
+version = "1.0.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d54378c645627613241d077a3a79db965db602882668f9136ac42af9ecb730ad"
+checksum = "e0f4a65597094d4483ddaed134f409b2cb7c1beccf25201a9f73c719254fa98e"
 dependencies = [
 "thiserror-impl",
 ]

 [[package]]
 name = "thiserror-impl"
-version = "1.0.56"
+version = "1.0.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa0faa943b50f3db30a20aa7e265dbc66076993efed8463e8de414e5d06d3471"
+checksum = "7765189610d8241a44529806d6fd1f2e0a08734313a35d5b3a556f92b381f3c0"
 dependencies = [
 "proc-macro2",
 "quote",
- "syn 2.0.48",
+ "syn",
 ]

 [[package]]
-name = "unicode-ident"
-version = "1.0.12"
+name = "thread_local"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
+checksum = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
+dependencies = [
+ "lazy_static",
+]

 [[package]]
-name = "utf8parse"
+name = "treeline"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7f741b240f1a48843f9b8e0444fb55fb2a4ff67293b50a9179dfd5ea67f8d41"
+
+[[package]]
+name = "unicode-width"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9337591893a19b88d8d87f2cec1e73fad5cdfd10e5a6f349f498ad6ea2ffb1e3"
+
+[[package]]
+name = "unicode-xid"
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "711b9620af191e0cdc7468a8d14e709c3dcdb115b36f838e601583af800a370a"
+checksum = "f7fe0bb3479651439c9112f72b6c505038574c9fbb575ed1bf3b797fa39dd564"
+
+[[package]]
+name = "vec_map"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1bddf1187be692e79c5ffeab891132dfb0f236ed36a43c7ed39f1165ee20191"

 [[package]]
 name = "wait-timeout"
@ -469,82 +347,29 @@ dependencies = [
 ]

 [[package]]
-name = "windows-sys"
-version = "0.52.0"
+name = "winapi"
+version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
 dependencies = [
- "windows-targets",
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
 ]

 [[package]]
-name = "windows-targets"
-version = "0.52.0"
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a18201040b24831fbb9e4eb208f8892e1f50a37feb53cc7ff887feb8f50e7cd"
-dependencies = [
- "windows_aarch64_gnullvm",
- "windows_aarch64_msvc",
- "windows_i686_gnu",
- "windows_i686_msvc",
- "windows_x86_64_gnu",
- "windows_x86_64_gnullvm",
- "windows_x86_64_msvc",
-]
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"

 [[package]]
-name = "windows_aarch64_gnullvm"
-version = "0.52.0"
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb7764e35d4db8a7921e09562a0304bf2f93e0a51bfccee0bd0bb0b666b015ea"
-
-[[package]]
-name = "windows_aarch64_msvc"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bbaa0368d4f1d2aaefc55b6fcfee13f41544ddf36801e793edbbfd7d7df075ef"
-
-[[package]]
-name = "windows_i686_gnu"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a28637cb1fa3560a16915793afb20081aba2c92ee8af57b4d5f28e4b3e7df313"
-
-[[package]]
-name = "windows_i686_msvc"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ffe5e8e31046ce6230cc7215707b816e339ff4d4d67c65dffa206fd0f7aa7b9a"
-
-[[package]]
-name = "windows_x86_64_gnu"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3d6fa32db2bc4a2f5abeacf2b69f7992cd09dca97498da74a151a3132c26befd"
-
-[[package]]
-name = "windows_x86_64_gnullvm"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1a657e1e9d3f514745a572a6846d3c7aa7dbe1658c056ed9c3344c4109a6949e"
-
-[[package]]
-name = "windows_x86_64_msvc"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dff9641d1cd4be8d1a070daf9e3773c5f67e78b4d9d42263020c057706765c04"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"

 [[package]]
 name = "xmlparser"
-version = "0.13.6"
+version = "0.13.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "66fee0b777b0f5ac1c69bb06d361268faafa61cd4682ae064a171c16c433e9e4"
-
-[[package]]
-name = "yaml-rust"
-version = "0.4.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
-dependencies = [
- "linked-hash-map",
-]
+checksum = "52613e655f6f11f63c0fe7d1c3b5ef69e44d96df9b65dab296b441ed0e1125f5"
--- a/Cargo.toml
+++ b/Cargo.toml
@ -5,4 +5,3 @@ members = [
  "opml_api",
  "opml_cli"
 ]
-resolver = "2"
--- a/2
+++ b/2
@ -1,6 +1,6 @@
 The MIT License

-Copyright (c) 2020-2024 Holllo <helllo@holllo.org>
+Copyright (c) 2020-2021 Holllo <helllo@holllo.cc>

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
--- a/Makefile.toml
+++ b/Makefile.toml
@ -1,31 +0,0 @@
-[env]
-CARGO_MAKE_EXTEND_WORKSPACE_MAKEFILE = true
-
-# Do a full check of everything.
-[tasks.complete-check]
-dependencies = [
-  "clean",
-  "format",
-  "check",
-  "clippy",
-  "test",
-  "code-coverage",
-  "docs",
-  "build",
-  "audit-flow",
-  "outdated-flow"
-]
-
-# Run cargo-tarpaulin and output the test coverage.
-[tasks.code-coverage]
-workspace = false
-command = "cargo"
-args = [
-  "tarpaulin",
-  "--exclude-files=target/*",
-  "--out=html",
-  "--output-dir=coverage",
-  "--skip-clean",
-  "--target-dir=target/tarpaulin",
-  "--workspace"
-]
--- a/README.md
+++ b/README.md
@ -1,31 +1,21 @@
-# OPML 📄
+# OPML

-> **OPML library for Rust & standalone CLI.**
+> An OPML parser for Rust and the command-line.

 ## API

-For API documentation and examples see [docs.rs](https://docs.rs/opml).
+For the API documentation, see [docs.rs](https://docs.rs/opml).

 ## CLI

-### Cargo
+To install the OPML command-line parser, run `cargo install opml_cli` or download a precompiled executable directly from [the Releases page](https://github.com/Holllo/opml/releases/latest).

-With a working [Rust and Cargo](https://www.rust-lang.org/learn/get-started) installation, you can install the OPML CLI from [Crates.io](https://crates.io/crates/opml_cli).
-
-```
-cargo install opml_cli
-```
-
-### Binaries
-
-Precompiled `x86_64-unknown-linux-gnu` binaries are available on the [Releases page](https://git.bauke.xyz/Holllo/opml/releases).
-
-## Development
-
-With [Nix flakes](https://nixos.wiki/wiki/Flakes) and [direnv](https://direnv.net/) installed and enabled, all the required dependencies are automatically loaded from [`shell.nix`](./shell.nix). Then [cargo-make](https://sagiegurari.github.io/cargo-make/) can be used to build, deploy and lint the code. The available tasks are all described in the [`Makefile.toml`](Makefile.toml) configuration.
+Then run `opml --help` to see all the available options.

 ## License

-Distributed under the [Apache License 2.0](https://spdx.org/licenses/Apache-2.0.html) and [MIT](https://spdx.org/licenses/MIT.html) licenses, see [LICENSE-Apache](https://git.bauke.xyz/Holllo/opml/src/branch/main/LICENSE-Apache) and [LICENSE-MIT](https://git.bauke.xyz/Holllo/opml/src/branch/main/LICENSE-MIT) for more information.
+Both the API and command-line parser are licensed under either of [Apache License, Version 2.0](https://github.com/Holllo/opml/blob/main/LICENSE-Apache) or [MIT license](https://github.com/Holllo/opml/blob/main/LICENSE-MIT) at your option.

-The samples located in `opml_api/tests/spec_samples`) were [taken from the OPML 2.0 spec](http://dev.opml.org/spec2.html#examples) and are subject to [their own license](https://git.bauke.xyz/Holllo/opml/src/branch/main/opml_api/tests/spec_samples/LICENSE).
+Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in either crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.
+
+The samples [located in `opml_api/tests/spec_samples`](https://github.com/Holllo/opml/tree/main/opml_api/tests/spec_samples) were [taken from the OPML 2.0 spec](http://dev.opml.org/spec2.html#examples) and are subject to [their own license](https://github.com/Holllo/opml/blob/main/opml_api/tests/spec_samples/LICENSE).
--- a/flake.lock
+++ b/flake.lock
@ -1,128 +0,0 @@
-{
-  "nodes": {
-    "flake-utils": {
-      "inputs": {
-        "systems": "systems"
-      },
-      "locked": {
-        "lastModified": 1705309234,
-        "narHash": "sha256-uNRRNRKmJyCRC/8y1RqBkqWBLM034y4qN7EprSdmgyA=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "1ef2e671c3b0c19053962c07dbda38332dcebf26",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
-    "flake-utils_2": {
-      "inputs": {
-        "systems": "systems_2"
-      },
-      "locked": {
-        "lastModified": 1681202837,
-        "narHash": "sha256-H+Rh19JDwRtpVPAWp64F+rlEtxUWBAQW28eAi3SRSzg=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "cfacdce06f30d2b68473a46042957675eebb3401",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
-    "nixpkgs": {
-      "locked": {
-        "lastModified": 1705697961,
-        "narHash": "sha256-XepT3WS516evSFYkme3GrcI3+7uwXHqtHbip+t24J7E=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "e5d1c87f5813afde2dda384ac807c57a105721cc",
-        "type": "github"
-      },
-      "original": {
-        "id": "nixpkgs",
-        "type": "indirect"
-      }
-    },
-    "nixpkgs_2": {
-      "locked": {
-        "lastModified": 1681358109,
-        "narHash": "sha256-eKyxW4OohHQx9Urxi7TQlFBTDWII+F+x2hklDOQPB50=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "96ba1c52e54e74c3197f4d43026b3f3d92e83ff9",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixpkgs-unstable",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "root": {
-      "inputs": {
-        "flake-utils": "flake-utils",
-        "nixpkgs": "nixpkgs",
-        "rust-overlay": "rust-overlay"
-      }
-    },
-    "rust-overlay": {
-      "inputs": {
-        "flake-utils": "flake-utils_2",
-        "nixpkgs": "nixpkgs_2"
-      },
-      "locked": {
-        "lastModified": 1705803528,
-        "narHash": "sha256-nChqKQPRXxmGBEkHse39LjNpkNKk4U1xPQ4a4oYlUdw=",
-        "owner": "oxalica",
-        "repo": "rust-overlay",
-        "rev": "bd7e8f4e122e11c934a576abc04327764f9bf19b",
-        "type": "github"
-      },
-      "original": {
-        "owner": "oxalica",
-        "repo": "rust-overlay",
-        "type": "github"
-      }
-    },
-    "systems": {
-      "locked": {
-        "lastModified": 1681028828,
-        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
-        "owner": "nix-systems",
-        "repo": "default",
-        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-systems",
-        "repo": "default",
-        "type": "github"
-      }
-    },
-    "systems_2": {
-      "locked": {
-        "lastModified": 1681028828,
-        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
-        "owner": "nix-systems",
-        "repo": "default",
-        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-systems",
-        "repo": "default",
-        "type": "github"
-      }
-    }
-  },
-  "root": "root",
-  "version": 7
-}
--- a/flake.nix
+++ b/flake.nix
@ -1,17 +0,0 @@
-{
-  inputs = {
-    flake-utils.url = "github:numtide/flake-utils";
-    rust-overlay.url = "github:oxalica/rust-overlay";
-  };
-
-  outputs = { self, nixpkgs, flake-utils, rust-overlay }:
-    flake-utils.lib.eachDefaultSystem (system:
-      let
-        overlays = [ (import rust-overlay) ];
-        pkgs = import nixpkgs { inherit system overlays; };
-      in
-      {
-        devShells.default = import ./shell.nix { inherit pkgs; };
-      }
-    );
-}
--- a/opml_api/Cargo.toml
+++ b/opml_api/Cargo.toml
@ -2,22 +2,20 @@

 [package]
 name = "opml"
-description = "OPML library for Rust."
-repository = "https://git.bauke.xyz/Holllo/opml"
+description = "An OPML parser for Rust."
+authors = ["Holllo <helllo@holllo.cc>"]
+version = "1.1.1"
 license = "MIT OR Apache-2.0"
-version = "1.1.6"
-authors = ["Holllo <helllo@holllo.org>"]
-edition = "2021"
+repository = "https://github.com/Holllo/opml"
 readme = "../README.md"
+edition = "2018"
 keywords = ["xml", "opml"]

 [lib]
 path = "source/lib.rs"

 [dependencies]
-hard-xml = "1.34.0"
-thiserror = "1.0.56"
-
-[dependencies.serde]
-version = "1.0.195"
-features = ["derive"]
+regex = "1.3"
+serde = { version = "1.0", features = ["derive"] }
+strong-xml = "0.6.2"
+thiserror = "1.0.24"
--- a/opml_api/LICENSE-MIT
+++ b/opml_api/LICENSE-MIT
@ -1,6 +1,6 @@
 The MIT License

-Copyright (c) 2020-2024 Holllo <helllo@holllo.org>
+Copyright (c) 2020-2021 Holllo <helllo@holllo.cc>

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
--- a/opml_api/examples/opml_samples/rust_feeds.opml
+++ b/opml_api/examples/opml_samples/rust_feeds.opml
--- a/opml_api/examples/rss.rs
+++ b/opml_api/examples/rss.rs
@ -1,31 +1,26 @@
+use std::{error::Error, fs};
+
 use opml::OPML;

-const SAMPLE: &str = r#"<opml version="2.0">
-<head>
-  <title>Rust Feeds</title>
-</head>
-<body>
-  <outline text="Rust Blog" xmlUrl="https://blog.rust-lang.org/feed.xml" />
-  <outline text="Inside Rust" xmlUrl="https://blog.rust-lang.org/inside-rust/feed.xml" />
-</body>
-</opml>"#;
+fn main() -> Result<(), Box<dyn Error>> {
+  let xml = fs::read_to_string("examples/opml_samples/rust_feeds.opml")?;

-/// Run this example using `cargo run --example rss`.
-///
-/// Output:
-/// Rust Feeds
-/// ──────────
-/// Rust Blog      https://blog.rust-lang.org/feed.xml
-/// Inside Rust    https://blog.rust-lang.org/inside-rust/feed.xml
-fn main() {
-  let subscriptions = OPML::from_str(SAMPLE).unwrap();
+  let subscriptions = OPML::from_str(&xml)?;
+  let head = subscriptions.head.unwrap();
+  let title = head.title.unwrap();

-  if let Some(title) = subscriptions.head.and_then(|head| head.title) {
-    println!("{}", title);
-    println!("{}", "-".repeat(title.len()));
-  }
+  println!(" {}", title);
+  println!(" {}", "─".repeat(title.len()));

  for outline in subscriptions.body.outlines {
-    println!("{}\t{}", outline.text, outline.xml_url.unwrap());
+    println!(" {}\t{}", outline.text, outline.xml_url.unwrap());
  }
+
+  Ok(())
 }
+
+// Output:
+// Rust Feeds
+// ──────────
+// Rust Blog      https://blog.rust-lang.org/feed.xml
+// Inside Rust    https://blog.rust-lang.org/inside-rust/feed.xml
--- a/opml_api/source/lib.rs
+++ b/opml_api/source/lib.rs
@ -1,86 +1,123 @@
-//! This crate provides an API to parse and create [OPML documents].
+//! This crate provides an API to parse and construct
+//! [OPML documents](http://dev.opml.org/spec2.html) to and from regular Rust
+//! structs.
 //!
-//! [OPML documents]: http://opml.org/spec2.opml
+//! ## Getting Started
 //!
-//! ## Parsing
+//! ### Parsing
 //!
-//! To parse an OPML document use [`OPML::from_str`] or [`OPML::from_reader`].
-//!
-//! Parsing will result in an error if:
-//! * the XML is malformed,
-//! * the included OPML version is not supported (currently all OPML versions
-//!   (1.0, 1.1 and 2.0) are supported) or,
-//! * if the [`Body`] element contains no child [`Outline`] elements,
-//!   [as per the spec].
-//!
-//! [as per the spec]: http://opml.org/spec2.opml#1629042198000
+//! Parsing XML into [an OPML struct](struct.OPML.html) can be done with
+//! [`OPML::new()`](struct.OPML.html#method.new). Resulting in an error if the
+//! XML can't be parsed, if the included OPML version is not supported
+//! (currently all OPML versions (1.0, 1.1 and 2.0) are supported) or if the
+//! [Body](struct.Body.html) element contains no child
+//! [Outline](struct.Outline.html) elements,
+//! [as per the spec](http://dev.opml.org/spec2.html#whatIsALtbodygt).
 //!
 //! ```rust
-//! use opml::OPML;
+//! use opml::{OPML, Outline};
 //!
 //! let xml = r#"<opml version="2.0"><head/><body><outline text="Outline"/></body></opml>"#;
-//! let document = OPML::from_str(xml).unwrap();
+//! let parsed = OPML::new(xml).unwrap();
 //!
-//! assert_eq!(document.version, "2.0");
+//! let mut expected = OPML::default();
+//! expected.body.outlines.push(Outline {
+//!   text: "Outline".to_string(),
+//!   ..Outline::default()
+//! });
+//!
+//! println!("{:#?}", parsed);
+//! assert_eq!(parsed, expected);
 //! ```
 //!
-//! ## Creating
+//! ### Constructing
 //!
-//! To create an OPML document from scratch, use [`OPML::default()`] or the good
-//! old `OPML { /* ... */ }` syntax.
+//! Constructing OPMLs is very easy as all you have to do is instantiate the
+//! [OPML struct](struct.OPML.html) with
+//! [`OPML::default()`](struct.OPML.html#method.default), add anything wanted
+//! and then call [`OPML::to_xml()`](struct.OPML.html#method.to_xml) to return
+//! the XML as a string.
+//!
+//! ```rust
+//! use opml::{Head, OPML};
+//!
+//! let mut opml = OPML::default();
+//! opml.head = Some(Head {
+//!   title: Some("Rust Feeds".to_string()),
+//!   ..Head::default()
+//! });
+//! opml
+//!   .add_feed("Rust Blog", "https://blog.rust-lang.org/feed.xml")
+//!   .add_feed(
+//!     "Inside Rust",
+//!     "https://blog.rust-lang.org/inside-rust/feed.xml",
+//!   );
+//!
+//! let xml = opml.to_xml().unwrap();
+//! let expected = r#"<opml version="2.0"><head><title>Rust Feeds</title></head><body><outline text="Rust Blog" xmlUrl="https://blog.rust-lang.org/feed.xml"/><outline text="Inside Rust" xmlUrl="https://blog.rust-lang.org/inside-rust/feed.xml"/></body></opml>"#;
+//! println!("{}", xml);
+//! assert_eq!(xml, expected);
+//! ```

-#![forbid(unsafe_code)]
-#![warn(missing_docs, clippy::missing_docs_in_private_items)]
-
-use hard_xml::{XmlRead, XmlWrite};
+use regex::Regex;
 use serde::{Deserialize, Serialize};
+use strong_xml::{XmlRead, XmlWrite};
 use thiserror::Error;

-/// All possible errors.
 #[derive(Debug, Error)]
 pub enum Error {
-  /// [From the spec], "a `<body>` contains one or more `<outline>` elements".
-  ///
-  /// [From the spec]: http://opml.org/spec2.opml#1629042198000
  #[error("OPML body has no <outline> elements")]
  BodyHasNoOutlines,

-  /// Wrapper for [`std::io::Error`].
  #[error("Failed to read file")]
  IoError(#[from] std::io::Error),

-  /// The version string in the XML is not supported.
  #[error("Unsupported OPML version: {0:?}")]
  UnsupportedVersion(String),

-  /// The input string is not valid XML.
  #[error("Failed to process XML file")]
-  XmlError(#[from] hard_xml::XmlError),
+  XmlError(#[from] strong_xml::XmlError),
 }

-/// The top-level [`OPML`] element.
+/// The top-level [OPML](struct.OPML.html) element.
 #[derive(
-  XmlWrite, XmlRead, PartialEq, Eq, Debug, Clone, Serialize, Deserialize,
+  XmlWrite, XmlRead, PartialEq, Debug, Clone, Serialize, Deserialize,
 )]
 #[xml(tag = "opml")]
 pub struct OPML {
-  /// The version attribute from the element, valid values are `1.0`, `1.1` and
-  /// `2.0`.
+  /// The version attribute from the element, valid values are `1.0`, `1.1` and `2.0`.
  #[xml(attr = "version")]
  pub version: String,

-  /// The [`Head`] child element. Contains the metadata of the OPML document.
+  /// The [Head](struct.Head.html) child element. Contains the metadata of the OPML document.
  #[xml(child = "head")]
  pub head: Option<Head>,

-  /// The [`Body`] child element. Contains all the [`Outline`] elements.
+  /// The [Body](struct.Body.html) child element. Contains all the [Outlines](struct.Outline.html).
  #[xml(child = "body")]
  pub body: Body,
 }

 impl OPML {
-  /// Deprecated, use [`OPML::from_str`] instead.
-  #[deprecated(note = "Use from_str instead", since = "1.1.0")]
+  /// Parses an OPML document.
+  ///
+  /// # Example
+  ///
+  /// ```rust
+  /// use opml::{OPML, Outline};
+  ///
+  /// let xml = r#"<opml version="2.0"><head/><body><outline text="Outline"/></body></opml>"#;
+  /// let parsed = OPML::new(xml).unwrap();
+  ///
+  /// let mut expected = OPML::default();
+  /// expected.body.outlines.push(Outline {
+  ///   text: "Outline".to_string(),
+  ///   ..Outline::default()
+  /// });
+  ///
+  /// assert_eq!(parsed, expected);
+  /// ```
+  #[deprecated(note = "use from_str instead", since = "1.1.0")]
  pub fn new(xml: &str) -> Result<Self, Error> {
    Self::from_str(xml).map_err(Into::into)
  }
@ -93,7 +130,7 @@ impl OPML {
  /// use opml::{OPML, Outline};
  ///
  /// let xml = r#"<opml version="2.0"><head/><body><outline text="Outline"/></body></opml>"#;
-  /// let document = OPML::from_str(xml).unwrap();
+  /// let parsed = OPML::from_str(xml).unwrap();
  ///
  /// let mut expected = OPML::default();
  /// expected.body.outlines.push(Outline {
@ -101,17 +138,21 @@ impl OPML {
  ///   ..Outline::default()
  /// });
  ///
-  /// assert_eq!(document, expected);
+  /// assert_eq!(parsed, expected);
  /// ```
  #[allow(clippy::should_implement_trait)]
  pub fn from_str(xml: &str) -> Result<Self, Error> {
    let opml = <OPML as XmlRead>::from_str(xml)?;

-    // SPEC: The version attribute is a version string, of the form, x.y, where
-    // x and y are both numeric strings.
-    let valid_versions = ["1.0", "1.1", "2.0"];
+    let version = &opml.version;

-    if !valid_versions.contains(&opml.version.as_str()) {
+    // SPEC: The version attribute is a version string, of the form, x.y, where x and y are both numeric strings.
+    let valid_version_regex = Regex::new(r"^\d+\.\d+$").unwrap();
+    let valid_versions = vec!["1.0", "1.1", "2.0"];
+
+    if !valid_version_regex.is_match(version)
+      || !valid_versions.contains(&version.as_str())
+    {
      return Err(Error::UnsupportedVersion(opml.version));
    }

@ -128,10 +169,11 @@ impl OPML {
  /// # Example
  ///
  /// ```rust,no_run
-  /// use opml::OPML;
+  /// use opml::{OPML, Outline};
+  /// use std::fs::File;
  ///
-  /// let mut file = std::fs::File::open("file.opml").unwrap();
-  /// let document = OPML::from_reader(&mut file).unwrap();
+  /// let mut file = File::open("file.opml").unwrap();
+  /// let parsed = OPML::from_reader(&mut file).unwrap();
  /// ```
  pub fn from_reader<R>(reader: &mut R) -> Result<Self, Error>
  where
@ -142,9 +184,7 @@ impl OPML {
    Self::from_str(&s).map_err(Into::into)
  }

-  /// Helper function to add an [`Outline`] element with `text` and `xml_url`
-  /// attributes to the [`Body`]. Useful for creating feed lists quickly.
-  /// This function also exists as [`Outline::add_feed`] for grouped lists.
+  /// Helper function to add an [Outline](struct.Outline.html) element with `text` and `xml_url` attributes to the [Body](struct.Body.html). Useful for creating feed lists quickly. This function [also exists on the Outline struct](struct.Outline.html#method.add_feed) to create grouped lists easily.
  ///
  /// # Example
  ///
@ -173,8 +213,20 @@ impl OPML {
    self
  }

-  /// Deprecated, use [`OPML::to_string`] instead.
-  #[deprecated(note = "Use to_string instead", since = "1.1.0")]
+  /// Converts the struct to an XML document.
+  ///
+  /// # Example
+  ///
+  /// ```rust
+  /// use opml::OPML;
+  ///
+  /// let opml = OPML::default();
+  /// let xml = opml.to_xml().unwrap();
+  ///
+  /// let expected = r#"<opml version="2.0"><head/><body/></opml>"#;
+  /// assert_eq!(xml, expected);
+  /// ```
+  #[deprecated(note = "Use to_string instead")]
  pub fn to_xml(&self) -> Result<String, Error> {
    self.to_string()
  }
@ -202,9 +254,10 @@ impl OPML {
  ///
  /// ```rust,no_run
  /// use opml::OPML;
+  /// use std::fs::File;
  ///
  /// let opml = OPML::default();
-  /// let mut file = std::fs::File::create("file.opml").unwrap();
+  /// let mut file = File::create("file.opml").unwrap();
  /// let xml = opml.to_writer(&mut file).unwrap();
  /// ```
  pub fn to_writer<W>(&self, writer: &mut W) -> Result<(), Error>
@ -212,7 +265,7 @@ impl OPML {
    W: std::io::Write,
  {
    let xml_string = self.to_string()?;
-    writer.write_all(xml_string.as_bytes())?;
+    writer.write_all(&xml_string.as_bytes())?;
    Ok(())
  }
 }
@ -227,18 +280,10 @@ impl Default for OPML {
  }
 }

-/// The [`Head`] child element of [`OPML`]. Contains the metadata of the OPML
-/// document.
+/// The [Head](struct.Head.html) child element of [OPML](struct.OPML.html).
+/// Contains the metadata of the OPML document.
 #[derive(
-  XmlWrite,
-  XmlRead,
-  PartialEq,
-  Eq,
-  Debug,
-  Clone,
-  Default,
-  Serialize,
-  Deserialize,
+  XmlWrite, XmlRead, PartialEq, Debug, Clone, Default, Serialize, Deserialize,
 )]
 #[xml(tag = "head")]
 pub struct Head {
@ -270,16 +315,11 @@ pub struct Head {
  #[xml(flatten_text = "docs")]
  pub docs: Option<String>,

-  /// A comma-separated list of line numbers that are expanded. The line numbers
-  /// in the list tell you which headlines to expand. The order is important.
-  /// For each element in the list, X, starting at the first summit, navigate
-  /// flatdown X times and expand. Repeat for each element in the list.
+  /// A comma-separated list of line numbers that are expanded. The line numbers in the list tell you which headlines to expand. The order is important. For each element in the list, X, starting at the first summit, navigate flatdown X times and expand. Repeat for each element in the list.
  #[xml(flatten_text = "expansionState")]
  pub expansion_state: Option<String>,

-  /// A number indicating which line of the outline is displayed on the top line
-  /// of the window. This number is calculated with the expansion state already
-  /// applied.
+  /// A number indicating which line of the outline is displayed on the top line of the window. This number is calculated with the expansion state already applied.
  #[xml(flatten_text = "vertScrollState")]
  pub vert_scroll_state: Option<i32>,

@ -300,80 +340,50 @@ pub struct Head {
  pub window_right: Option<i32>,
 }

-/// The [`Body`] child element of [`OPML`]. Contains all the [`Outline`]
-/// elements.
+/// The [Body](struct.Body.html) child element of [OPML](struct.OPML.html). Contains all the [Outlines](struct.Outline.html).
 #[derive(
-  XmlWrite,
-  XmlRead,
-  PartialEq,
-  Eq,
-  Debug,
-  Clone,
-  Default,
-  Serialize,
-  Deserialize,
+  XmlWrite, XmlRead, PartialEq, Debug, Clone, Default, Serialize, Deserialize,
 )]
 #[xml(tag = "body")]
 pub struct Body {
-  /// All the top-level [`Outline`] elements.
+  /// All the top-level [Outline](struct.Outline.html) elements.
  #[xml(child = "outline")]
  pub outlines: Vec<Outline>,
 }

-/// The [`Outline`] element.
+/// The [Outline](struct.Outline.html) element.
 #[derive(
-  XmlWrite,
-  XmlRead,
-  PartialEq,
-  Eq,
-  Debug,
-  Clone,
-  Default,
-  Serialize,
-  Deserialize,
+  XmlWrite, XmlRead, PartialEq, Debug, Clone, Default, Serialize, Deserialize,
 )]
 #[xml(tag = "outline")]
 pub struct Outline {
-  /// Every outline element must have at least a text attribute, which is what
-  /// is displayed when an outliner opens the OPML document.
-  ///
-  /// Version 1.0 OPML documents may omit this attribute, so for compatibility
-  /// and strictness this attribute is "technically optional" as it will be
-  /// replaced by an empty String if it is omitted.
-  ///
+  /// Every outline element must have at least a text attribute, which is what is displayed when an outliner opens the OPML document.
+  /// Version 1.0 OPML documents may omit this attribute, so for compatibility and strictness this attribute is "technically optional" as it will be replaced by an empty String if it is omitted.
  /// Text attributes may contain encoded HTML markup.
  #[xml(default, attr = "text")]
  pub text: String,

-  /// A string that indicates how the other attributes of the [`Outline`]
-  /// should be interpreted.
+  /// A string that indicates how the other attributes of the [Outline](struct.Outline.html) should be interpreted.
  #[xml(attr = "type")]
  pub r#type: Option<String>,

-  /// Indicating whether the outline is commented or not. By convention if an
-  /// outline is commented, all subordinate outlines are considered to also be
-  /// commented.
+  /// Indicating whether the outline is commented or not. By convention if an outline is commented, all subordinate outlines are considered to also be commented.
  #[xml(attr = "isComment")]
  pub is_comment: Option<bool>,

-  /// Indicating whether a breakpoint is set on this outline. This attribute is
-  /// mainly necessary for outlines used to edit scripts.
+  /// Indicating whether a breakpoint is set on this outline. This attribute is mainly necessary for outlines used to edit scripts.
  #[xml(attr = "isBreakpoint")]
  pub is_breakpoint: Option<bool>,

-  /// The date-time (RFC822) that this [`Outline`] element was created.
+  /// The date-time (RFC822) that this [Outline](struct.Outline.html) element was created.
  #[xml(attr = "created")]
  pub created: Option<String>,

-  /// A string of comma-separated slash-delimited category strings, in the
-  /// format defined by the [RSS 2.0 category] element. To represent a "tag",
-  /// the category string should contain no slashes.
-  ///
-  /// [RSS 2.0 category]: https://cyber.law.harvard.edu/rss/rss.html#ltcategorygtSubelementOfLtitemgt
+  /// A string of comma-separated slash-delimited category strings, in the format defined by the [RSS 2.0 category](http://cyber.law.harvard.edu/rss/rss.html#ltcategorygtSubelementOfLtitemgt) element. To represent a "tag," the category string should contain no slashes.
  #[xml(attr = "category")]
  pub category: Option<String>,

-  /// Child [`Outline`] elements of the current one.
+  /// Child [Outline](struct.Outline.html) elements of the current one.
  #[xml(child = "outline")]
  pub outlines: Vec<Outline>,

@ -401,21 +411,18 @@ pub struct Outline {
  #[xml(attr = "version")]
  pub version: Option<String>,

-  /// A link that can point to another OPML document or to something that can
-  /// be displayed in a web browser.
+  /// A link that can point to another OPML document or to something that can be displayed in a web browser.
  #[xml(attr = "url")]
  pub url: Option<String>,
 }

 impl Outline {
-  /// Helper function to add an [`Outline`] element with `text` and `xml_url`
-  /// attributes as a child element, useful for creating grouped lists. This
-  /// function also exists as [`OPML::add_feed`] for non-grouped lists.
+  /// Helper function to add an [Outline](struct.Outline.html) element with `text` and `xml_url` attributes as a child element. Useful for creating grouped lists. This function [also exists on the OPML struct](struct.OPML.html#method.add_feed) for non-grouped lists.
  ///
  /// # Example
  ///
  /// ```rust
-  /// use opml::Outline;
+  /// use opml::{Outline};
  ///
  /// let mut group = Outline::default();
  /// group.add_feed("Feed Name", "https://example.com/");
--- a/opml_api/tests/deprecated.rs
+++ b/opml_api/tests/deprecated.rs
@ -1,11 +0,0 @@
-use opml::OPML;
-
-#[test]
-#[allow(deprecated)]
-fn test_deprecated_functions() {
-  let xml = r#"<opml version="2.0"><head/><body><outline text="Outline"/></body></opml>"#;
-  let document = OPML::new(xml).unwrap();
-
-  assert_eq!(document.version, "2.0");
-  assert!(document.to_xml().is_ok());
-}
--- a/opml_api/tests/samples/empty_docs.opml
+++ b/opml_api/tests/samples/empty_docs.opml
@ -1,8 +0,0 @@
-<opml version="2.0">
-  <head>
-    <docs />
-  </head>
-  <body>
-    <outline text="Outline Text"/>
-  </body>
-</opml>
--- a/opml_api/tests/spec_samples.rs
+++ b/opml_api/tests/spec_samples.rs
@ -14,7 +14,7 @@ pub fn test_spec_samples() -> Result<(), Box<dyn Error>> {
  ];

  for sample in samples {
-    let sample_content = fs::read_to_string(sample)?;
+    let sample_content = fs::read_to_string(&sample)?;
    OPML::from_str(&sample_content)?;
  }

--- a/opml_api/tests/valid.rs
+++ b/opml_api/tests/valid.rs
@ -20,26 +20,6 @@ fn test_minimum_valid_opml() {
  );
 }

-#[test]
-fn test_valid_empty_docs() {
-  assert_eq!(
-    OPML::from_str(&read("tests/samples/empty_docs.opml").unwrap()).unwrap(),
-    OPML {
-      version: "2.0".to_string(),
-      head: Some(Head {
-        docs: Some("".to_string()),
-        ..Head::default()
-      }),
-      body: Body {
-        outlines: vec![Outline {
-          text: "Outline Text".to_string(),
-          ..Outline::default()
-        }]
-      },
-    }
-  )
-}
-
 #[test]
 fn test_valid_opml_with_everything() {
  assert_eq!(
@ -119,17 +99,3 @@ fn test_valid_opml_1_0() {
    }
  );
 }
-
-#[test]
-fn test_valid_from_reader() {
-  let xml = r#"<opml version="2.0"><head/><body><outline text="Outline"/></body></opml>"#;
-  assert!(OPML::from_reader(&mut xml.as_bytes()).is_ok());
-}
-
-#[test]
-fn test_valid_to_writer() {
-  let document = OPML::default();
-  let mut writer = vec![];
-  assert!(document.to_writer(&mut writer).is_ok());
-  assert!(!writer.is_empty());
-}
--- a/opml_cli/Cargo.toml
+++ b/opml_cli/Cargo.toml
@ -2,13 +2,13 @@

 [package]
 name = "opml_cli"
-description = "OPML for the command-line."
-repository = "https://git.bauke.xyz/Holllo/opml"
+description = "An OPML parser for the command-line."
+version = "1.1.1"
+authors = ["Holllo <helllo@holllo.cc>"]
 license = "MIT OR Apache-2.0"
-version = "1.1.6"
-authors = ["Holllo <helllo@holllo.org>"]
-edition = "2021"
+repository = "https://github.com/Holllo/opml"
 readme = "../README.md"
+edition = "2018"
 keywords = ["xml", "opml"]

 [[bin]]
@ -16,21 +16,13 @@ name = "opml"
 path = "source/main.rs"

 [dependencies]
-serde_json = "1.0.111"
-
-[dependencies.clap]
-version = "4.4.18"
-features = ["derive"]
-
-[dependencies.opml]
-path = "../opml_api"
-version = "1.1.5"
+clap = "2.33"
+opml = { path = "../opml_api", version = "1.1.1" }
+serde_json = "1.0"

 [dependencies.serde]
-version = "1.0.195"
+version = "1.0"
 features = ["derive"]

 [dev-dependencies]
-assert_cmd = "2.0.13"
-insta = "1.34.0"
-test-case = "3.3.1"
+assert_cmd = "1.0"
--- a/opml_cli/LICENSE-MIT
+++ b/opml_cli/LICENSE-MIT
@ -1,6 +1,6 @@
 The MIT License

-Copyright (c) 2020-2024 Holllo <helllo@holllo.org>
+Copyright (c) 2020-2021 Holllo <helllo@holllo.cc>

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
--- a/opml_cli/source/main.rs
+++ b/opml_cli/source/main.rs
@ -1,43 +1,70 @@
-use std::{fs::read_to_string, path::PathBuf};
+use std::fs::read_to_string;

-use clap::Parser;
+use clap::{
+  crate_authors, crate_description, crate_version, App, Arg, ArgGroup,
+};
 use opml::{Outline, OPML};

-#[derive(Debug, Parser)]
-#[clap(about, author, version)]
-struct Args {
-  /// The OPML file to parse.
-  #[clap(short, long)]
-  file: PathBuf,
-
-  /// Output the OPML as JSON.
-  #[clap(long, group = "format", required = true)]
-  json: bool,
-
-  /// Output the OPML as pretty-printed JSON.
-  #[clap(long, group = "format", required = true)]
-  json_pretty: bool,
-
-  /// Only output the outline text and xmlUrl attributes when both are present
-  /// in the outline element.
-  #[clap(long, group = "format", required = true)]
-  rss: bool,
-
-  /// Print extra information while running.
-  #[clap(long)]
-  verbose: bool,
-}
-
 fn main() {
-  let args = Args::parse();
+  let cli = App::new("OPML CLI")
+    .about(crate_description!())
+    .author(crate_authors!())
+    .version(crate_version!())
+    .args(&[
+      // Format flags.
+      Arg::with_name("json")
+        .long("json")
+        .long_help("Output the OPML as JSON.")
+        .takes_value(false),
+      Arg::with_name("json pretty")
+        .long("json-pretty")
+        .long_help("Output the OPML as pretty-printed JSON.")
+        .takes_value(false),
+      Arg::with_name("rss")
+        .long("rss")
+        .long_help(
+          "Only output the outline text and xmlUrl attributes \
+          when both are present in the outline element.",
+        )
+        .takes_value(false),
+      // Boolean flags.
+      Arg::with_name("verbose")
+        .long("verbose")
+        .long_help("Print extra information while running.")
+        .takes_value(false),
+      // Options that are only allowed once.
+      Arg::with_name("file")
+        .long("file")
+        .long_help("The OPML file to parse.")
+        .required(true)
+        .short("f")
+        .takes_value(true),
+    ])
+    .group(
+      ArgGroup::with_name("format")
+        .args(&["json", "json pretty", "rss"])
+        .required(true),
+    )
+    .get_matches();
+
+  // Extract format flags.
+  let json = cli.is_present("json");
+  let json_pretty = cli.is_present("json pretty");
+  let rss = cli.is_present("rss");
+
+  // Extract boolean flags.
+  let verbose = cli.is_present("verbose");
+
+  // Extract the various options.
+  let file = cli.value_of("file").unwrap();

  // Read the file to string.
-  let xml = read_to_string(args.file).expect("Failed to read OPML file");
+  let xml = read_to_string(file).expect("Failed to read OPML file");

  // Parse the OPML from the read file.
  let opml = OPML::from_str(&xml).expect("Failed to parse OPML file");

-  if args.rss {
+  if rss {
    // Get all the outlines from the OPML document.
    let outlines = extract_all_outlines(&opml.body.outlines);

@ -46,19 +73,19 @@ fn main() {
      if let Some(xml_url) = outline.xml_url {
        println!("{}", outline.text);
        println!("{}", xml_url);
-      } else if args.verbose {
+      } else if verbose {
        println!(
          "Skipping \"{}\" because it did not have an xmlUrl attribute.",
          outline.text
        );
      }
    }
-  } else if args.json {
+  } else if json {
    println!(
      "{}",
      serde_json::to_string(&opml).expect("Failed to convert OPML to JSON")
    );
-  } else if args.json_pretty {
+  } else if json_pretty {
    println!(
      "{}",
      serde_json::to_string_pretty(&opml)
--- a/opml_cli/tests/cli.rs
+++ b/opml_cli/tests/cli.rs
@ -1,25 +0,0 @@
-use {
-  assert_cmd::Command, insta::assert_display_snapshot, test_case::test_case,
-};
-
-const SAMPLE: &str = "tests/sample.opml";
-
-#[test_case(&["--file", SAMPLE, "--json"], "json" ; "json")]
-#[test_case(&["--file", SAMPLE, "--json-pretty"], "json_pretty" ; "json_pretty")]
-#[test_case(&["--file", SAMPLE, "--rss"], "rss" ; "rss")]
-fn test_valid(args: &[&str], name: &str) {
-  let mut cmd = Command::cargo_bin("opml").unwrap();
-  let assert = cmd.args(args).assert().success().code(0);
-  let output = String::from_utf8(assert.get_output().stdout.clone()).unwrap();
-  assert_display_snapshot!(name, output);
-}
-
-#[test_case(&["--rss"], "missing_file" ; "missing_file")]
-#[test_case(&["--file", SAMPLE], "missing_format" ; "missing_format")]
-#[test_case(&["--rss", "--json"], "multiple_formats" ; "multiple_formats")]
-fn test_invalid(args: &[&'static str], name: &str) {
-  let mut cmd = Command::cargo_bin("opml").unwrap();
-  let assert = cmd.args(args).assert().failure().code(2);
-  let output = String::from_utf8(assert.get_output().stderr.clone()).unwrap();
-  assert_display_snapshot!(name, output);
-}
--- a/opml_cli/tests/invalid.rs
+++ b/opml_cli/tests/invalid.rs
@ -0,0 +1,27 @@
+use std::fs::read_to_string;
+
+use assert_cmd::Command;
+
+const SAMPLE: &str = "tests/samples/youtube.opml";
+
+#[test]
+fn test_missing_file() {
+  let mut cmd = Command::cargo_bin("opml").unwrap();
+  let assert = cmd.args(&["--rss"]).assert();
+
+  assert
+    .failure()
+    .code(1)
+    .stderr(read_to_string("tests/snapshots/missing-file.txt").unwrap());
+}
+
+#[test]
+fn test_missing_format() {
+  let mut cmd = Command::cargo_bin("opml").unwrap();
+  let assert = cmd.args(&["--file", SAMPLE]).assert();
+
+  assert
+    .failure()
+    .code(1)
+    .stderr(read_to_string("tests/snapshots/missing-format.txt").unwrap());
+}
--- a/opml_cli/tests/samples/youtube.opml
+++ b/opml_cli/tests/samples/youtube.opml
@ -0,0 +1,15 @@
+<opml version="1.1">
+  <body>
+    <outline text="YouTube Subscriptions"
+      title="YouTube Subscriptions">
+      <outline text="A YouTube Channel"
+        title="A YouTube Channel"
+        type="rss"
+        xmlUrl="https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz1" />
+      <outline text="Another YouTube Channel"
+        title="Another YouTube Channel"
+        type="rss"
+        xmlUrl="https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz2" />
+    </outline>
+  </body>
+</opml>
--- a/opml_cli/tests/snapshots/cli__json.snap
+++ b/opml_cli/tests/snapshots/cli__json.snap
@ -1,6 +0,0 @@
---
-source: opml_cli/tests/cli.rs
-expression: output
---
-{"version":"2.0","head":{"title":"Rust Feeds","date_created":null,"date_modified":null,"owner_name":null,"owner_email":null,"owner_id":null,"docs":null,"expansion_state":null,"vert_scroll_state":null,"window_top":null,"window_left":null,"window_bottom":null,"window_right":null},"body":{"outlines":[{"text":"Rust Blog","type":null,"is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[],"xml_url":"https://blog.rust-lang.org/feed.xml","description":null,"html_url":null,"language":null,"title":null,"version":null,"url":null},{"text":"Inside Rust","type":null,"is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[],"xml_url":"https://blog.rust-lang.org/inside-rust/feed.xml","description":null,"html_url":null,"language":null,"title":null,"version":null,"url":null}]}}
-
--- a/opml_cli/tests/snapshots/cli__json_pretty.snap
+++ b/opml_cli/tests/snapshots/cli__json_pretty.snap
@ -1,59 +0,0 @@
---
-source: opml_cli/tests/cli.rs
-expression: output
---
-{
-  "version": "2.0",
-  "head": {
-    "title": "Rust Feeds",
-    "date_created": null,
-    "date_modified": null,
-    "owner_name": null,
-    "owner_email": null,
-    "owner_id": null,
-    "docs": null,
-    "expansion_state": null,
-    "vert_scroll_state": null,
-    "window_top": null,
-    "window_left": null,
-    "window_bottom": null,
-    "window_right": null
-  },
-  "body": {
-    "outlines": [
-      {
-        "text": "Rust Blog",
-        "type": null,
-        "is_comment": null,
-        "is_breakpoint": null,
-        "created": null,
-        "category": null,
-        "outlines": [],
-        "xml_url": "https://blog.rust-lang.org/feed.xml",
-        "description": null,
-        "html_url": null,
-        "language": null,
-        "title": null,
-        "version": null,
-        "url": null
-      },
-      {
-        "text": "Inside Rust",
-        "type": null,
-        "is_comment": null,
-        "is_breakpoint": null,
-        "created": null,
-        "category": null,
-        "outlines": [],
-        "xml_url": "https://blog.rust-lang.org/inside-rust/feed.xml",
-        "description": null,
-        "html_url": null,
-        "language": null,
-        "title": null,
-        "version": null,
-        "url": null
-      }
-    ]
-  }
-}
-
--- a/opml_cli/tests/snapshots/cli__missing_file.snap
+++ b/opml_cli/tests/snapshots/cli__missing_file.snap
@ -1,13 +0,0 @@
---
-source: opml_cli/tests/cli.rs
-expression: output
---
-error: the following required arguments were not provided:
-  --file <FILE>
-  --json
-  --json-pretty
-
-Usage: opml --file <FILE> --json --json-pretty --rss
-
-For more information, try '--help'.
-
--- a/opml_cli/tests/snapshots/cli__missing_format.snap
+++ b/opml_cli/tests/snapshots/cli__missing_format.snap
@ -1,13 +0,0 @@
---
-source: opml_cli/tests/cli.rs
-expression: output
---
-error: the following required arguments were not provided:
-  --json
-  --json-pretty
-  --rss
-
-Usage: opml --file <FILE> --json --json-pretty --rss
-
-For more information, try '--help'.
-
--- a/opml_cli/tests/snapshots/cli__multiple_formats.snap
+++ b/opml_cli/tests/snapshots/cli__multiple_formats.snap
@ -1,10 +0,0 @@
---
-source: opml_cli/tests/cli.rs
-expression: output
---
-error: the argument '--rss' cannot be used with '--json'
-
-Usage: opml --file <FILE> --json --json-pretty --rss
-
-For more information, try '--help'.
-
--- a/opml_cli/tests/snapshots/cli__rss.snap
+++ b/opml_cli/tests/snapshots/cli__rss.snap
@ -1,9 +0,0 @@
---
-source: opml_cli/tests/cli.rs
-expression: output
---
-Rust Blog
-https://blog.rust-lang.org/feed.xml
-Inside Rust
-https://blog.rust-lang.org/inside-rust/feed.xml
-
--- a/opml_cli/tests/snapshots/json-pretty.json
+++ b/opml_cli/tests/snapshots/json-pretty.json
@ -0,0 +1,57 @@
+{
+  "version": "1.1",
+  "head": null,
+  "body": {
+    "outlines": [
+      {
+        "text": "YouTube Subscriptions",
+        "type": null,
+        "is_comment": null,
+        "is_breakpoint": null,
+        "created": null,
+        "category": null,
+        "outlines": [
+          {
+            "text": "A YouTube Channel",
+            "type": "rss",
+            "is_comment": null,
+            "is_breakpoint": null,
+            "created": null,
+            "category": null,
+            "outlines": [],
+            "xml_url": "https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz1",
+            "description": null,
+            "html_url": null,
+            "language": null,
+            "title": "A YouTube Channel",
+            "version": null,
+            "url": null
+          },
+          {
+            "text": "Another YouTube Channel",
+            "type": "rss",
+            "is_comment": null,
+            "is_breakpoint": null,
+            "created": null,
+            "category": null,
+            "outlines": [],
+            "xml_url": "https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz2",
+            "description": null,
+            "html_url": null,
+            "language": null,
+            "title": "Another YouTube Channel",
+            "version": null,
+            "url": null
+          }
+        ],
+        "xml_url": null,
+        "description": null,
+        "html_url": null,
+        "language": null,
+        "title": "YouTube Subscriptions",
+        "version": null,
+        "url": null
+      }
+    ]
+  }
+}
--- a/opml_cli/tests/snapshots/json.json
+++ b/opml_cli/tests/snapshots/json.json
@ -0,0 +1 @@
+{"version":"1.1","head":null,"body":{"outlines":[{"text":"YouTube Subscriptions","type":null,"is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[{"text":"A YouTube Channel","type":"rss","is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[],"xml_url":"https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz1","description":null,"html_url":null,"language":null,"title":"A YouTube Channel","version":null,"url":null},{"text":"Another YouTube Channel","type":"rss","is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[],"xml_url":"https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz2","description":null,"html_url":null,"language":null,"title":"Another YouTube Channel","version":null,"url":null}],"xml_url":null,"description":null,"html_url":null,"language":null,"title":"YouTube Subscriptions","version":null,"url":null}]}}
--- a/opml_cli/tests/snapshots/missing-file.txt
+++ b/opml_cli/tests/snapshots/missing-file.txt
@ -0,0 +1,7 @@
+error: The following required arguments were not provided:
+    --file <file>
+
+USAGE:
+    opml --file <file> <--json|--json-pretty|--rss>
+
+For more information try --help
--- a/opml_cli/tests/snapshots/missing-format.txt
+++ b/opml_cli/tests/snapshots/missing-format.txt
@ -0,0 +1,7 @@
+error: The following required arguments were not provided:
+    <--json|--json-pretty|--rss>
+
+USAGE:
+    opml [FLAGS] --file <file> <--json|--json-pretty|--rss>
+
+For more information try --help
--- a/opml_cli/tests/snapshots/rss.txt
+++ b/opml_cli/tests/snapshots/rss.txt
@ -0,0 +1,4 @@
+A YouTube Channel
+https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz1
+Another YouTube Channel
+https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz2
--- a/opml_cli/tests/valid.rs
+++ b/opml_cli/tests/valid.rs
@ -0,0 +1,38 @@
+use std::fs::read_to_string;
+
+use assert_cmd::Command;
+
+const SAMPLE: &str = "tests/samples/youtube.opml";
+
+#[test]
+fn test_valid_rss() {
+  let mut cmd = Command::cargo_bin("opml").unwrap();
+  let assert = cmd.args(&["--file", SAMPLE, "--rss"]).assert();
+
+  assert
+    .success()
+    .code(0)
+    .stdout(read_to_string("tests/snapshots/rss.txt").unwrap());
+}
+
+#[test]
+fn test_valid_json() {
+  let mut cmd = Command::cargo_bin("opml").unwrap();
+  let assert = cmd.args(&["--file", SAMPLE, "--json"]).assert();
+
+  assert
+    .success()
+    .code(0)
+    .stdout(read_to_string("tests/snapshots/json.json").unwrap());
+}
+
+#[test]
+fn test_valid_json_pretty() {
+  let mut cmd = Command::cargo_bin("opml").unwrap();
+  let assert = cmd.args(&["--file", SAMPLE, "--json-pretty"]).assert();
+
+  assert
+    .success()
+    .code(0)
+    .stdout(read_to_string("tests/snapshots/json-pretty.json").unwrap());
+}
--- a/rustup-toolchain.toml
+++ b/rustup-toolchain.toml
@ -1,3 +0,0 @@
-[toolchain]
-channel = "stable"
-components = ["cargo", "clippy", "rustfmt", "rust-src"]
--- a/shell.nix
+++ b/shell.nix
@ -1,18 +0,0 @@
-{ pkgs ? import <nixpkgs> { } }:
-
-with pkgs;
-
-let
-  rustup-toolchain = rust-bin.fromRustupToolchainFile ./rustup-toolchain.toml;
-in
-mkShell rec {
-  packages = [
-    cargo-audit
-    cargo-edit
-    cargo-insta
-    cargo-make
-    cargo-outdated
-    cargo-tarpaulin
-    rustup-toolchain
-  ];
-}
				`@ -0,0 +1 @@`
				{"version":"1.1","head":null,"body":{"outlines":[{"text":"YouTube Subscriptions","type":null,"is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[{"text":"A YouTube Channel","type":"rss","is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[],"xml_url":"https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz1","description":null,"html_url":null,"language":null,"title":"A YouTube Channel","version":null,"url":null},{"text":"Another YouTube Channel","type":"rss","is_comment":null,"is_breakpoint":null,"created":null,"category":null,"outlines":[],"xml_url":"https://www.youtube.com/feeds/videos.xml?channel_id=abcdefghijklmnopqrstuvwxyz2","description":null,"html_url":null,"language":null,"title":"Another YouTube Channel","version":null,"url":null}],"xml_url":null,"description":null,"html_url":null,"language":null,"title":"YouTube Subscriptions","version":null,"url":null}]}}