feat: YAML naming-only 言語サポート + ベストプラクティスドキュメント (#76)

* [test] YAML E2E テスト・fixture・CI dogfooding 追加 because of naming-only 言語サポート

- tests/e2e_yaml.rs: 7テスト (happy path, naming violation, name_targets)
- tests/fixtures/yaml_sample/: fixture (config + manifests レイヤー)
- ci.yml: dogfood-rust に YAML fixture ステップ追加

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* [fix] YAML パーサー実装 + DispatchingParser 登録 because of naming-only 言語サポート

- tree-sitter-yaml 0.6 追加
- YamlParser: キー→Symbol, 値→StringLiteral, コメント→Comment
- ext_to_language に yaml/yml 追加
- SOURCE_EXTENSIONS に yaml/yml 追加
- E2E テスト 7/7 通過

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* [refactor] YAML サポートのドキュメント追加 because of PR #76 完了

- Website: YAML ガイド (ja/en) + ベストプラクティス (ja/en)
- astro.config.mjs: サイドバーに YAML + ベストプラクティス追加
- index.mdx: 言語リストに YAML 追加 (ja/en)
- README.md: Languages/Configuration Reference/設定例に YAML 追加
- docs/TODO.md: YAML サポート完了記録
- docs/e2e_checklist.md: YAML naming-only 注記追加

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: makinzm

.github/workflows/ci.yml

@@ -147,6 +147,9 @@ jobs:
       - name: Self-check — C fixture (tests/fixtures/c_sample)
         working-directory: tests/fixtures/c_sample
         run: ${{ github.workspace }}/target/release/mille check
+      - name: Self-check — YAML fixture (tests/fixtures/yaml_sample)
+        working-directory: tests/fixtures/yaml_sample
+        run: ${{ github.workspace }}/target/release/mille check
 
   # ------------------------------------------------------------------ #
   # 3b. Dogfooding-python — maturin build → pytest + mille check     #

Cargo.lock

@@ -37,6 +37,7 @@ serde_json = "1"
 tree-sitter-kotlin = "0.3"
 tree-sitter-php = "0.22"
 tree-sitter-c = "0.21"
+tree-sitter-yaml = "0.6"
 
 [dev-dependencies]
 tempfile = "3"

Cargo.toml

@@ -8,7 +8,7 @@ One TOML config. Rust-powered. CI-ready. Supports multiple languages from a sing
 
 ## What it checks
 
-**Languages:** Rust, Go, TypeScript, JavaScript, Python, Java, Kotlin, PHP, C
+**Languages:** Rust, Go, TypeScript, JavaScript, Python, Java, Kotlin, PHP, C, YAML
 
 | Check | Description |
 |---|---|
@@ -415,7 +415,7 @@ Exit codes:
 |---|---|
 | `name` | Project name |
 | `root` | Root directory for analysis |
-| `languages` | Languages to check: `"rust"`, `"go"`, `"typescript"`, `"javascript"`, `"python"`, `"java"`, `"kotlin"`, `"php"`, `"c"` |
+| `languages` | Languages to check: `"rust"`, `"go"`, `"typescript"`, `"javascript"`, `"python"`, `"java"`, `"kotlin"`, `"php"`, `"c"`, `"yaml"` |
 
 ### `[[layers]]`
 
@@ -466,7 +466,7 @@ name_deny_ignore = ["**/test_*.rs", "tests/**"]  # exclude test files from namin
   - `"comment"`: inline comment content
   - `"string_literal"`: string literal content
   - `"identifier"`: attribute/field access identifiers (e.g. `gcp` in `cfg.gcp.bucket`)
-- Supported languages: Rust, TypeScript, JavaScript, Python, Go, Java, Kotlin, PHP, C
+- Supported languages: Rust, TypeScript, JavaScript, Python, Go, Java, Kotlin, PHP, C, YAML
 - Severity is controlled by `severity.naming_violation` (default: `"error"`)
 
 ### `[[layers.allow_call_patterns]]`
@@ -653,6 +653,32 @@ dependency_mode = "opt-in"
 allow = ["domain"]
 ```
 
+### YAML
+
+> YAML is a **naming-only** language — it has no imports, so only `name_deny` checks are supported. `dependency_mode` and `external_mode` should be set to `"opt-out"`.
+
+**Example `mille.toml` for YAML config files:**
+
+```toml
+[project]
+name    = "my-k8s-project"
+root    = "."
+languages = ["yaml"]
+
+[[layers]]
+name      = "config"
+paths     = ["config/**"]
+dependency_mode = "opt-out"
+external_mode   = "opt-out"
+name_deny = ["aws", "gcp"]
+
+[[layers]]
+name      = "manifests"
+paths     = ["manifests/**"]
+dependency_mode = "opt-out"
+external_mode   = "opt-out"
+```
+
 ## How it Works
 
 mille uses [tree-sitter](https://tree-sitter.github.io/) for AST-based import extraction — no regex heuristics.
@@ -663,7 +689,7 @@ mille.toml
     ▼
 Layer definitions
     │
-Source files (*.rs, *.go, *.py, *.ts, *.js, *.java, ...)
+Source files (*.rs, *.go, *.py, *.ts, *.js, *.java, *.yaml, ...)
     │ tree-sitter parse
     ▼
 RawImport list

README.md

@@ -36,6 +36,7 @@
 - ✅ PHP 言語サポート — `.php` ファイルの `use` 文パース（simple/aliased/grouped/function/const）・Internal/External/Stdlib 分類、`[resolve.php] namespace` 設定、`composer.json` `autoload.psr-4` 自動検出、PHP stdlib クラス（DateTime/PDO/Exception 等）の Stdlib 自動分類
 
 - ✅ PATH 位置引数 — 全サブコマンドに `[PATH]` 位置引数を追加（デフォルト `.`）。`mille check ./other/project` で任意ディレクトリを検査可能。`CommonArgs` + `Command::common()` exhaustive match で新コマンド追加時にコンパイルエラーで PATH 対応を強制（PR #75）
+- ✅ YAML 言語サポート — naming-only 言語として `.yaml`/`.yml` ファイルの `name_deny` チェックをサポート。マッピングキー→Symbol、スカラー値→StringLiteral、コメント→Comment として抽出。tree-sitter-yaml 0.6 使用（PR #76）
 
 以下は **設定ファイルにフィールドが存在しても、まだ動作していない** 項目です（README に掲載しないよう修正済み）：
 （現在なし）

docs/TODO.md

@@ -17,3 +17,18 @@
 - [ ] external opt-in: `external_allow = []` → 外部違反
 - [ ] external opt-out: `external_deny` を設定 → 外部違反
 - [ ] allow_call_patterns: 禁止メソッド呼び出し → `CallPatternViolation`
+
+---
+
+## 言語固有の注記
+
+### YAML (naming-only)
+
+YAML は import の概念がないため、以下の項目は N/A:
+- dep opt-in / dep opt-out: N/A
+- external opt-in / external opt-out: N/A
+- allow_call_patterns: N/A
+
+YAML で有効なチェック:
+- [x] name_deny: キー (Symbol) と値 (StringLiteral) の命名チェック
+- [x] name_targets: `["symbol"]` / `["string_literal"]` で対象の絞り込み

docs/e2e_checklist.md

@@ -6,6 +6,7 @@ pub mod php;
 pub mod python;
 pub mod rust;
 pub mod typescript;
+pub mod yaml;
 
 use self::c::CParser;
 use self::go::GoParser;
@@ -15,6 +16,7 @@ use self::php::PhpParser;
 use self::python::PythonParser;
 use self::rust::RustParser;
 use self::typescript::TypeScriptParser;
+use self::yaml::YamlParser;
 use crate::domain::entity::call_expr::RawCallExpr;
 use crate::domain::entity::import::RawImport;
 use crate::domain::entity::name::{NameKind, ParsedNames, RawName};
@@ -106,6 +108,7 @@ pub fn ext_to_language(ext: &str) -> Option<&'static str> {
         "kt" => Some("kotlin"),
         "php" => Some("php"),
         "c" | "h" => Some("c"),
+        "yaml" | "yml" => Some("yaml"),
         _ => None,
     }
 }
@@ -120,6 +123,7 @@ pub struct DispatchingParser {
     java: JavaParser,
     kotlin: KotlinParser,
     php: PhpParser,
+    yaml: YamlParser,
 }
 
 impl DispatchingParser {
@@ -133,6 +137,7 @@ impl DispatchingParser {
             java: JavaParser,
             kotlin: KotlinParser,
             php: PhpParser,
+            yaml: YamlParser,
         }
     }
 }
@@ -143,6 +148,10 @@ impl Default for DispatchingParser {
     }
 }
 
+fn is_yaml(file_path: &str) -> bool {
+    file_path.ends_with(".yaml") || file_path.ends_with(".yml")
+}
+
 fn is_c(file_path: &str) -> bool {
     file_path.ends_with(".c") || file_path.ends_with(".h")
 }
@@ -156,7 +165,9 @@ fn is_ts_js(file_path: &str) -> bool {
 
 impl Parser for DispatchingParser {
     fn parse_imports(&self, source: &str, file_path: &str) -> Vec<RawImport> {
-        if is_c(file_path) {
+        if is_yaml(file_path) {
+            self.yaml.parse_imports(source, file_path)
+        } else if is_c(file_path) {
             self.c.parse_imports(source, file_path)
         } else if file_path.ends_with(".go") {
             self.go.parse_imports(source, file_path)
@@ -176,7 +187,9 @@ impl Parser for DispatchingParser {
     }
 
     fn parse_call_exprs(&self, source: &str, file_path: &str) -> Vec<RawCallExpr> {
-        if is_c(file_path) {
+        if is_yaml(file_path) {
+            self.yaml.parse_call_exprs(source, file_path)
+        } else if is_c(file_path) {
             self.c.parse_call_exprs(source, file_path)
         } else if file_path.ends_with(".go") {
             self.go.parse_call_exprs(source, file_path)
@@ -196,7 +209,9 @@ impl Parser for DispatchingParser {
     }
 
     fn parse_names(&self, source: &str, file_path: &str) -> ParsedNames {
-        if is_c(file_path) {
+        if is_yaml(file_path) {
+            self.yaml.parse_names(source, file_path)
+        } else if is_c(file_path) {
             self.c.parse_names(source, file_path)
         } else if file_path.ends_with(".go") {
             self.go.parse_names(source, file_path)