feat(rules): add ocr rules check command to preview effective rule for a file path

README.md

@@ -103,6 +103,7 @@ ocr review --commit abc123
 | Command | Alias | Description |
 |---------|-------|-------------|
 | `ocr review` | `ocr r` | Start a code review |
+| `ocr rules check <file>` | — | Preview which review rule applies to a file path |
 | `ocr config set <key> <value>` | — | Set configuration values |
 | `ocr llm test` | — | Test LLM connectivity |
 | `ocr viewer` | `ocr v` | Launch WebUI session viewer on `localhost:5483` |
@@ -138,6 +139,10 @@ ocr review --commit abc123 --format json --audience agent
 # Use custom review rules
 ocr review --rule /path/to/my-rules.json
 
+# Preview which rule applies to a file
+ocr rules check src/main/java/com/example/Foo.java
+ocr rules check --rule custom.json src/main/resources/mapper/UserMapper.xml
+
 # View review session history in browser
 ocr viewer
 ocr viewer --addr :3000

README.zh-CN.md

@@ -103,6 +103,7 @@ ocr review --commit abc123
 | 命令 | 别名 | 描述 |
 |------|------|------|
 | `ocr review` | `ocr r` | 开始代码审查 |
+| `ocr rules check <file>` | — | 预览某个文件路径生效的审查规则 |
 | `ocr config set <key> <value>` | — | 设置配置项 |
 | `ocr llm test` | — | 测试 LLM 连通性 |
 | `ocr viewer` | `ocr v` | 启动 WebUI 会话查看器，地址 `localhost:5483` |
@@ -138,6 +139,10 @@ ocr review --commit abc123 --format json --audience agent
 # 使用自定义审查规则
 ocr review --rule /path/to/my-rules.json
 
+# 预览某个文件路径生效的规则
+ocr rules check src/main/java/com/example/Foo.java
+ocr rules check --rule custom.json src/main/resources/mapper/UserMapper.xml
+
 # 在浏览器中查看审查会话历史
 ocr viewer
 ocr viewer --addr :3000

cmd/opencodereview/main.go

@@ -50,6 +50,8 @@ func dispatch() error {
 		return runConfig(args[1:])
 	case "llm":
 		return runLLM(args[1:])
+	case "rules":
+		return runRules(args[1:])
 	case "viewer":
 		return runViewer(args[1:])
 	case "-h", "--help":
@@ -68,9 +70,10 @@ Usage:
 
 Commands:
   review, r    Start a code review
+  rules        Inspect and debug review rules
   config       Manage configuration settings
   llm          LLM utility commands
-  viewer    Start the WebUI session viewer
+  viewer       Start the WebUI session viewer
   version      Show version information
 
 Examples:
@@ -81,6 +84,7 @@ Examples:
   ocr version                              Show version info
 
 Use "ocr review -h" for more information about review.
+Use "ocr rules -h" for more information about rules.
 Use "ocr config" for more information about config.
 Use "ocr llm" for more information about LLM utilities.`)
 }

cmd/opencodereview/rules_cmd.go

@@ -0,0 +1,104 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/open-code-review/open-code-review/internal/config/rules"
+)
+
+func runRules(args []string) error {
+	if len(args) == 0 {
+		printRulesUsage()
+		return nil
+	}
+	switch args[0] {
+	case "check":
+		return runRulesCheck(args[1:])
+	case "-h", "--help":
+		printRulesUsage()
+		return nil
+	default:
+		return fmt.Errorf("unknown rules sub-command: %s\nRun 'ocr rules -h' for usage", args[0])
+	}
+}
+
+func runRulesCheck(args []string) error {
+	a := newOcrFlagSet("ocr rules check")
+	var repoDir, rulePath string
+	a.StringVar(&repoDir, "repo", "", "root directory of the git repository (default: current dir)")
+	a.StringVar(&rulePath, "rule", "", "path to JSON file with custom review rules")
+	if err := a.Parse(args); err != nil {
+		return err
+	}
+	if a.showHelp {
+		printRulesCheckUsage()
+		return nil
+	}
+
+	rest := a.fs.Args()
+	if len(rest) == 0 {
+		printRulesCheckUsage()
+		return nil
+	}
+	filePath := rest[0]
+
+	resolvedRepo, err := resolveRepoDir(repoDir)
+	if err != nil {
+		return err
+	}
+
+	resolver, _, err := rules.NewResolver(resolvedRepo, rulePath)
+	if err != nil {
+		return fmt.Errorf("load rules: %w", err)
+	}
+
+	dr, ok := resolver.(rules.DetailResolver)
+	if !ok {
+		return fmt.Errorf("resolver does not support detail inspection")
+	}
+
+	detail := dr.ResolveDetail(strings.ToLower(filePath))
+
+	sourceLabel := map[string]string{
+		"custom":  "Custom (--rule)",
+		"project": "Project (.opencodereview/rule.json)",
+		"global":  "Global (~/.opencodereview/rule.json)",
+		"system":  "System built-in",
+	}
+
+	fmt.Printf("File: %s\n", filePath)
+	fmt.Printf("Source: %s\n", sourceLabel[detail.Source])
+	fmt.Printf("Pattern: %s\n", detail.Pattern)
+	fmt.Println("Rule:")
+	fmt.Println(strings.Repeat("─", 40))
+	fmt.Println(detail.Rule)
+	fmt.Println(strings.Repeat("─", 40))
+
+	return nil
+}
+
+func printRulesUsage() {
+	fmt.Println(`Usage:
+  ocr rules <sub-command>
+
+Sub-commands:
+  check <file>   Show which review rule applies to a given file path
+
+Use "ocr rules check -h" for more information.`)
+}
+
+func printRulesCheckUsage() {
+	fmt.Println(`Usage:
+  ocr rules check [flags] <file-path>
+
+Show which review rule applies to the given file path, including its source layer and matched pattern.
+
+Flags:
+  --repo    Root directory of the git repository (default: current dir)
+  --rule    Path to a custom rule JSON file
+
+Examples:
+  ocr rules check src/main/java/com/example/Foo.java
+  ocr rules check --rule custom.json src/main/resources/mapper/UserMapper.xml`)
+}

internal/config/rules/system_rules.go

@@ -108,6 +108,18 @@ func LoadDefault() (*SystemRule, error) {
 	return &rule, nil
 }
 
+// RuleDetail contains the resolved rule along with metadata about its source.
+type RuleDetail struct {
+	Rule    string // rule text
+	Source  string // "custom" | "project" | "global" | "system"
+	Pattern string // glob pattern that matched, or "default" for fallback
+}
+
+// DetailResolver extends Resolver with source metadata.
+type DetailResolver interface {
+	ResolveDetail(path string) RuleDetail
+}
+
 // Resolve returns the rule text for a given file path.
 // Patterns with brace expansion like "*.{go,py}" are expanded into "*.go", "*.py".
 // The first match wins; if none match, it falls back to DefaultRule.
@@ -124,6 +136,18 @@ func (r *SystemRule) Resolve(path string) string {
 	return r.DefaultRule
 }
 
+func (r *SystemRule) resolveDetail(path string) RuleDetail {
+	for _, pr := range r.PathRules {
+		expanded := expandBraces(pr.Pattern)
+		for _, p := range expanded {
+			if matched, _ := doublestar.Match(p, path); matched {
+				return RuleDetail{Rule: pr.Rule, Source: "system", Pattern: pr.Pattern}
+			}
+		}
+	}
+	return RuleDetail{Rule: r.DefaultRule, Source: "system", Pattern: "default"}
+}
+
 // expandBraces turns "{a,b,c}" style patterns into individual strings.
 // e.g. "*.go.{java,kotlin}" → ["*.go.java", "*.go.kotlin"].
 // If no braces exist, returns the original pattern unchanged.
@@ -340,6 +364,20 @@ func (c *composedResolver) Resolve(path string) string {
 	return c.system.Resolve(path)
 }
 
+// ResolveDetail returns the matched rule along with its source layer and pattern.
+func (c *composedResolver) ResolveDetail(path string) RuleDetail {
+	if detail := matchProjectRuleDetail(c.custom, path, "custom"); detail != nil {
+		return *detail
+	}
+	if detail := matchProjectRuleDetail(c.project, path, "project"); detail != nil {
+		return *detail
+	}
+	if detail := matchProjectRuleDetail(c.global, path, "global"); detail != nil {
+		return *detail
+	}
+	return c.system.resolveDetail(path)
+}
+
 func matchProjectRule(pr *ProjectRule, path string) string {
 	if pr == nil {
 		return ""
@@ -354,3 +392,21 @@ func matchProjectRule(pr *ProjectRule, path string) string {
 	}
 	return ""
 }
+
+func matchProjectRuleDetail(pr *ProjectRule, path, source string) *RuleDetail {
+	if pr == nil {
+		return nil
+	}
+	for _, entry := range pr.Rules {
+		if entry.Rule == "" {
+			continue
+		}
+		expanded := expandBraces(entry.Path)
+		for _, p := range expanded {
+			if matched, _ := doublestar.Match(p, path); matched {
+				return &RuleDetail{Rule: entry.Rule, Source: source, Pattern: entry.Path}
+			}
+		}
+	}
+	return nil
+}

internal/config/rules/system_rules_test.go

@@ -521,6 +521,116 @@ func TestNewResolver_FileFilterFallsToProject(t *testing.T) {
 	}
 }
 
+func TestResolveDetail_SystemDefault(t *testing.T) {
+	resolver, _, err := NewResolver(t.TempDir(), "")
+	if err != nil {
+		t.Fatalf("NewResolver: %v", err)
+	}
+	dr := resolver.(DetailResolver)
+
+	detail := dr.ResolveDetail("readme.md")
+	if detail.Source != "system" {
+		t.Errorf("expected source 'system', got %q", detail.Source)
+	}
+	if detail.Pattern != "default" {
+		t.Errorf("expected pattern 'default', got %q", detail.Pattern)
+	}
+	if !strings.Contains(detail.Rule, "Correctness") {
+		t.Errorf("expected default rule content, got %q", truncate(detail.Rule, 80))
+	}
+}
+
+func TestResolveDetail_SystemPatternMatch(t *testing.T) {
+	t.Setenv("HOME", t.TempDir())
+	resolver, _, err := NewResolver(t.TempDir(), "")
+	if err != nil {
+		t.Fatalf("NewResolver: %v", err)
+	}
+	dr := resolver.(DetailResolver)
+
+	detail := dr.ResolveDetail("src/main/foo.java")
+	if detail.Source != "system" {
+		t.Errorf("expected source 'system', got %q", detail.Source)
+	}
+	if detail.Pattern != "**/*.java" {
+		t.Errorf("expected pattern '**/*.java', got %q", detail.Pattern)
+	}
+	if !strings.Contains(detail.Rule, "逻辑错误识别") {
+		t.Errorf("expected java rule, got %q", truncate(detail.Rule, 80))
+	}
+}
+
+func TestResolveDetail_ProjectOverridesSystem(t *testing.T) {
+	t.Setenv("HOME", t.TempDir())
+	dir := t.TempDir()
+	ocrDir := filepath.Join(dir, ".opencodereview")
+	if err := os.MkdirAll(ocrDir, 0o755); err != nil {
+		t.Fatalf("mkdir: %v", err)
+	}
+	ruleJSON := `{"rules":[{"path":"src/**/*.java","rule":"project-java-rule"}]}`
+	if err := os.WriteFile(filepath.Join(ocrDir, "rule.json"), []byte(ruleJSON), 0o644); err != nil {
+		t.Fatalf("write: %v", err)
+	}
+
+	resolver, _, err := NewResolver(dir, "")
+	if err != nil {
+		t.Fatalf("NewResolver: %v", err)
+	}
+	dr := resolver.(DetailResolver)
+
+	detail := dr.ResolveDetail("src/main/foo.java")
+	if detail.Source != "project" {
+		t.Errorf("expected source 'project', got %q", detail.Source)
+	}
+	if detail.Pattern != "src/**/*.java" {
+		t.Errorf("expected pattern 'src/**/*.java', got %q", detail.Pattern)
+	}
+	if detail.Rule != "project-java-rule" {
+		t.Errorf("expected 'project-java-rule', got %q", detail.Rule)
+	}
+
+	// Unmatched path falls to system
+	detail = dr.ResolveDetail("other/bar.java")
+	if detail.Source != "system" {
+		t.Errorf("expected source 'system', got %q", detail.Source)
+	}
+}
+
+func TestResolveDetail_CustomOverridesAll(t *testing.T) {
+	// Project rule
+	repoDir := t.TempDir()
+	ocrDir := filepath.Join(repoDir, ".opencodereview")
+	if err := os.MkdirAll(ocrDir, 0o755); err != nil {
+		t.Fatalf("mkdir: %v", err)
+	}
+	projJSON := `{"rules":[{"path":"**/*.java","rule":"project-java-rule"}]}`
+	if err := os.WriteFile(filepath.Join(ocrDir, "rule.json"), []byte(projJSON), 0o644); err != nil {
+		t.Fatalf("write: %v", err)
+	}
+
+	// Custom rule (highest priority)
+	customDir := t.TempDir()
+	customJSON := `{"rules":[{"path":"**/*.java","rule":"custom-java-rule"}]}`
+	customPath := filepath.Join(customDir, "custom.json")
+	if err := os.WriteFile(customPath, []byte(customJSON), 0o644); err != nil {
+		t.Fatalf("write: %v", err)
+	}
+
+	resolver, _, err := NewResolver(repoDir, customPath)
+	if err != nil {
+		t.Fatalf("NewResolver: %v", err)
+	}
+	dr := resolver.(DetailResolver)
+
+	detail := dr.ResolveDetail("src/foo.java")
+	if detail.Source != "custom" {
+		t.Errorf("expected source 'custom', got %q", detail.Source)
+	}
+	if detail.Rule != "custom-java-rule" {
+		t.Errorf("expected 'custom-java-rule', got %q", detail.Rule)
+	}
+}
+
 func TestNewResolver_BraceExpansionInProjectRule(t *testing.T) {
 	dir := t.TempDir()
 	ocrDir := filepath.Join(dir, ".opencodereview")