Linter: Add support for defining custom Linter rules

javascript/packages/formatter/src/cli.ts

@@ -5,6 +5,7 @@ import { resolve, relative } from "path"
 
 import { Herb } from "@herb-tools/node-wasm"
 import { Config, addHerbExtensionRecommendation, getExtensionsJsonRelativePath } from "@herb-tools/config"
+import { colorize } from "@herb-tools/highlighter"
 
 import { Formatter } from "./formatter.js"
 import { ASTRewriter, StringRewriter, CustomRewriterLoader, builtinRewriters, isASTRewriterClass, isStringRewriterClass } from "@herb-tools/rewriter/loader"
@@ -208,7 +209,19 @@ export class CLI {
         allRewriterClasses.push(...builtinRewriters)
 
         const loader = new CustomRewriterLoader({ baseDir })
-        const { rewriters: customRewriters, duplicateWarnings } = await loader.loadRewritersWithInfo()
+        const { rewriters: customRewriters, rewriterInfo, duplicateWarnings } = await loader.loadRewritersWithInfo()
+
+        if (customRewriters.length > 0) {
+          console.error(colorize(`\nLoaded ${customRewriters.length} custom ${pluralize(customRewriters.length, 'rewriter')}:`, "green"))
+
+          for (const { name, path } of rewriterInfo) {
+            const relativePath = config.projectPath ? path.replace(config.projectPath + '/', '') : path
+
+            console.error(colorize(`  • ${name}`, "cyan") + colorize(` (${relativePath})`, "dim"))
+          }
+
+          console.error()
+        }
 
         allRewriterClasses.push(...customRewriters)
         warnings.push(...duplicateWarnings)
@@ -274,18 +287,41 @@ export class CLI {
         }
 
         if (preRewriters.length > 0 || postRewriters.length > 0) {
-          const parts: string[] = []
+          const customRewriterPaths = new Map(rewriterInfo.map(r => [r.name, r.path]))
 
           if (preRewriters.length > 0) {
-            parts.push(`${preRewriters.length} pre-format ${pluralize(preRewriters.length, 'rewriter')}: ${rewriterNames.pre.join(', ')}`)
+            console.error(colorize(`\nUsing ${preRewriters.length} pre-format ${pluralize(preRewriters.length, 'rewriter')}:`, "green"))
+
+            for (const rewriter of preRewriters) {
+              const customPath = customRewriterPaths.get(rewriter.name)
+
+              if (customPath) {
+                const relativePath = config.projectPath ? customPath.replace(config.projectPath + '/', '') : customPath
+                console.error(colorize(`  • ${rewriter.name}`, "cyan") + colorize(` (${relativePath})`, "dim"))
+              } else {
+                console.error(colorize(`  • ${rewriter.name}`, "cyan") + colorize(` (built-in)`, "dim"))
+              }
+            }
+
+            console.error()
           }
 
           if (postRewriters.length > 0) {
-            parts.push(`${postRewriters.length} post-format ${pluralize(postRewriters.length, 'rewriter')}: ${rewriterNames.post.join(', ')}`)
-          }
+            console.error(colorize(`\nUsing ${postRewriters.length} post-format ${pluralize(postRewriters.length, 'rewriter')}:`, "green"))
 
-          console.error(`Using ${parts.join(', ')}`)
-          console.error()
+            for (const rewriter of postRewriters) {
+              const customPath = customRewriterPaths.get(rewriter.name)
+
+              if (customPath) {
+                const relativePath = config.projectPath ? customPath.replace(config.projectPath + '/', '') : customPath
+                console.error(colorize(`  • ${rewriter.name}`, "cyan") + colorize(` (${relativePath})`, "dim"))
+              } else {
+                console.error(colorize(`  • ${rewriter.name}`, "cyan") + colorize(` (built-in)`, "dim"))
+              }
+            }
+
+            console.error()
+          }
         }
 
         if (warnings.length > 0) {

javascript/packages/formatter/test/cli/rewriters.test.ts

@@ -5,6 +5,15 @@ import { join } from "path"
 
 import { execBinary, expectExitCode, } from "./cli-helpers"
 
+/**
+ * Normalizes stderr output by replacing absolute paths with relative paths
+ * This makes snapshots consistent across different environments (local vs CI)
+ */
+function normalizeStderr(stderr: string): string {
+  const cwd = process.cwd()
+  return stderr.replace(new RegExp(cwd + '/', 'g'), '')
+}
+
 describe("CLI", () => {
   describe("Rewriters", () => {
     const testDir = "test-rewriters"
@@ -35,7 +44,7 @@ describe("CLI", () => {
       const result = await execBinary([testFile])
 
       expectExitCode(result, 0)
-      expect(result.stderr).toContain("Using 1 pre-format rewriter: tailwind-class-sorter")
+      expect(normalizeStderr(result.stderr)).toMatchSnapshot()
     })
 
     it("should show multiple rewriters on stderr", async () => {
@@ -55,7 +64,7 @@ describe("CLI", () => {
       const result = await execBinary([testFile])
 
       expectExitCode(result, 0)
-      expect(result.stderr).toContain("Using 1 pre-format rewriter: tailwind-class-sorter")
+      expect(normalizeStderr(result.stderr)).toMatchSnapshot()
     })
 
     it("should actually apply Tailwind class sorting", async () => {
@@ -77,7 +86,7 @@ describe("CLI", () => {
       const result = await execBinary([testFile])
 
       expectExitCode(result, 0)
-      expect(result.stdout).toContain("Formatted: test-rewriters/test.html.erb")
+      expect(normalizeStderr(result.stderr)).toMatchSnapshot()
 
       const formattedContent = await readFile(testFile, 'utf-8')
       expect(formattedContent).toBe(`<div class="rounded bg-blue-500 px-4 text-white"></div>\n`)
@@ -98,8 +107,8 @@ describe("CLI", () => {
       const result = await execBinary(["--config-file", configPath], input)
 
       expectExitCode(result, 0)
-      expect(result.stderr).toContain(`Using 1 pre-format rewriter: tailwind-class-sorter`)
-      expect(result.stdout).toContain(`class="bg-blue-500 px-4 text-white"`)
+      expect(normalizeStderr(result.stderr)).toMatchSnapshot()
+      expect(result.stdout).toMatchSnapshot()
     })
 
     it("should show warning for unknown rewriters on stderr", async () => {
@@ -119,9 +128,7 @@ describe("CLI", () => {
       const result = await execBinary([testFile])
 
       expectExitCode(result, 0)
-      expect(result.stderr).toContain("⚠️")
-      expect(result.stderr).toContain("non-existent-rewriter")
-      expect(result.stderr).toContain("not found")
+      expect(normalizeStderr(result.stderr)).toMatchSnapshot()
     })
 
     it("should not show rewriter info when no rewriters are configured", async () => {
@@ -138,9 +145,7 @@ describe("CLI", () => {
       const result = await execBinary([testFile])
 
       expectExitCode(result, 0)
-      expect(result.stderr).not.toContain("pre-format rewriter")
-      expect(result.stderr).not.toContain("post-format rewriter")
-      expect(result.stderr).toContain("⚠️  Experimental Preview")
+      expect(normalizeStderr(result.stderr)).toMatchSnapshot()
     })
 
     it("should handle both pre and post rewriters", async () => {
@@ -160,8 +165,7 @@ describe("CLI", () => {
       const result = await execBinary([testFile])
 
       expectExitCode(result, 0)
-      expect(result.stderr).toContain("Using 1 pre-format rewriter: tailwind-class-sorter")
-      expect(result.stderr).not.toContain("post-format")
+      expect(normalizeStderr(result.stderr)).toMatchSnapshot()
     })
   })
 })

javascript/packages/formatter/test/rewriters/fixtures/uppercase-tags.js

@@ -30,7 +30,7 @@ class UppercaseTagsVisitor extends Visitor {
   }
 }
 
-export class UppercaseTagsRewriter extends ASTRewriter {
+export default class UppercaseTagsRewriter extends ASTRewriter {
   get name() {
     return "uppercase-tags"
   }