feat: allow TypeScript parsing to be safe related to JSX syntax limit…

…ations
antoine-coulon · Oct 25, 2022 · 80fc92f · 80fc92f
1 parent 96313c5
commit 80fc92f
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Showing 2 changed files with 63 additions and 18 deletions.
diff --git a/packages/skott/src/modules/walkers/ecmascript/typescript/walker.ts b/packages/skott/src/modules/walkers/ecmascript/typescript/walker.ts
@@ -4,30 +4,55 @@ import { ModuleWalker, ModuleWalkerResult } from "../../common.js";
 import { isCommonJSModuleImport } from "../javascript/cjs.js";
 import { isEcmaScriptModuleDeclaration } from "../module-declaration.js";
 
-/**
- * TypeScript implements the ECMAScript standard module system. This walker
- * is nearly the same as the JavaScript walker, minus the CJS support which
- * is not needed here.
- */
+async function tryOrElse(
+  tryFn: () => void,
+  orElseFn: () => void
+): Promise<void> {
+  try {
+    await tryFn();
+
+    return;
+  } catch {}
+
+  try {
+    orElseFn();
+  } catch {}
+}
+
 export class TypeScriptModuleWalker implements ModuleWalker {
   public async walk(fileContent: string): Promise<ModuleWalkerResult> {
     const { parse } = await import("@typescript-eslint/typescript-estree");
     const moduleDeclarations = new Set<string>();
-    const node = parse(fileContent, { jsx: true, loc: false, comment: false });
-    const isRootNode = node.type === "Program";
+    let jsxEnabled = true;
 
-    walk(isRootNode ? node.body : node, {
-      enter(node) {
-        if (isCommonJSModuleImport(node)) {
-          moduleDeclarations.add(node.arguments[0].value);
-        }
-        if (isEcmaScriptModuleDeclaration(node)) {
-          moduleDeclarations.add(node.source.value);
-        }
-        if (node.type === "ImportExpression") {
-          moduleDeclarations.add(node.source.value);
+    function processWalk(): void {
+      const node = parse(fileContent, {
+        jsx: jsxEnabled,
+        loc: false,
+        comment: false
+      });
+      const isRootNode = node.type === "Program";
+
+      walk(isRootNode ? node.body : node, {
+        enter(node) {
+          if (isCommonJSModuleImport(node)) {
+            moduleDeclarations.add(node.arguments[0].value);
+          }
+          if (isEcmaScriptModuleDeclaration(node)) {
+            moduleDeclarations.add(node.source.value);
+          }
+          if (node.type === "ImportExpression") {
+            moduleDeclarations.add(node.source.value);
+          }
         }
-      }
+      });
+    }
+
+    await tryOrElse(processWalk, () => {
+      // Retry without JSX enabled
+      jsxEnabled = false;
+
+      return processWalk();
     });
 
     return { moduleDeclarations };

diff --git a/packages/skott/test/ecmascript/jsx-and-tsx.ts b/packages/skott/test/ecmascript/jsx-and-tsx.ts
@@ -165,3 +165,23 @@ export function makeTestSuiteForJsxOrTsx(rawLanguage: "ts" | "js"): void {
     });
   });
 }
+
+describe("When some TypeScript code is not TSX compliant", () => {
+  it("should be able to parse the script disabling the jsx feature", async () => {
+    const fileThatCanNotBeParsedAsTSX = `
+    export const unparsableTSXFunction = async <T>(
+      x: T
+    ) => {}
+    `;
+
+    mountFakeFileSystem({
+      "index.ts": fileThatCanNotBeParsedAsTSX
+    });
+
+    const { files } = await buildSkottProjectUsingInMemoryFileExplorer({
+      entrypoint: "index.ts"
+    });
+
+    expect(files).to.deep.equal(["index.ts"]);
+  });
+});