Cherry-pick PR #34906 into release-3.7 (#35006)

Component commits:
dfa4bc0d75 Use empty object for invalid package json contents instead of undefined Fixes #34726

4d035ba5f8 Behave as if package json doesnt exist in case of invalid json in package json

src/server/packageJsonCache.ts

@@ -9,7 +9,7 @@ namespace ts.server {
     }
 
     export function createPackageJsonCache(project: Project): PackageJsonCache {
-        const packageJsons = createMap<PackageJsonInfo>();
+        const packageJsons = createMap<PackageJsonInfo | false>();
         const directoriesWithoutPackageJson = createMap<true>();
         return {
             addOrUpdate,
@@ -18,7 +18,7 @@ namespace ts.server {
                 directoriesWithoutPackageJson.set(getDirectoryPath(fileName), true);
             },
             getInDirectory: directory => {
-                return packageJsons.get(combinePaths(directory, "package.json"));
+                return packageJsons.get(combinePaths(directory, "package.json")) || undefined;
             },
             directoryHasPackageJson,
             searchDirectoryAndAncestors: directory => {
@@ -39,7 +39,7 @@ namespace ts.server {
 
         function addOrUpdate(fileName: Path) {
             const packageJsonInfo = createPackageJsonInfo(fileName, project);
-            if (packageJsonInfo) {
+            if (packageJsonInfo !== undefined) {
                 packageJsons.set(fileName, packageJsonInfo);
                 directoriesWithoutPackageJson.delete(getDirectoryPath(fileName));
             }

src/server/project.ts

@@ -1471,7 +1471,8 @@ namespace ts.server {
                     case Ternary.True:
                         const packageJsonFileName = combinePaths(directory, "package.json");
                         watchPackageJsonFile(packageJsonFileName);
-                        result.push(Debug.assertDefined(packageJsonCache.getInDirectory(directory)));
+                        const info = packageJsonCache.getInDirectory(directory);
+                        if (info) result.push(info);
                 }
                 if (rootPath && rootPath === toPath(directory)) {
                     return true;

src/services/utilities.ts

@@ -2210,7 +2210,7 @@ namespace ts {
         return packageJsons;
     }
 
-    export function createPackageJsonInfo(fileName: string, host: LanguageServiceHost): PackageJsonInfo | undefined {
+    export function createPackageJsonInfo(fileName: string, host: LanguageServiceHost): PackageJsonInfo | false | undefined {
         if (!host.readFile) {
             return undefined;
         }
@@ -2218,11 +2218,10 @@ namespace ts {
         type PackageJsonRaw = Record<typeof dependencyKeys[number], Record<string, string> | undefined>;
         const dependencyKeys = ["dependencies", "devDependencies", "optionalDependencies", "peerDependencies"] as const;
         const stringContent = host.readFile(fileName);
-        const content = stringContent && tryParseJson(stringContent) as PackageJsonRaw;
-        if (!content) {
-            return undefined;
-        }
+        if (!stringContent) return undefined;
 
+        const content = tryParseJson(stringContent) as PackageJsonRaw;
+        if (!content) return false;
         const info: Pick<PackageJsonInfo, typeof dependencyKeys[number]> = {};
         for (const key of dependencyKeys) {
             const dependencies = content[key];

src/testRunner/unittests/tsserver/packageJsonInfo.ts

@@ -71,6 +71,23 @@ namespace ts.projectSystem {
             assert.lengthOf(project.getPackageJsonsVisibleToFile("/a.ts" as Path), 1);
             assert.lengthOf(project.getPackageJsonsVisibleToFile("/src/b.ts" as Path), 2);
         });
+
+        it("handles errors in json parsing of package.json", () => {
+            const packageJsonContent = `{ "mod" }`;
+            const { project, host } = setup([tsConfig, { path: packageJson.path, content: packageJsonContent }]);
+            project.getPackageJsonsVisibleToFile("/src/whatever/blah.ts" as Path);
+            const packageJsonInfo = project.packageJsonCache.getInDirectory("/" as Path)!;
+            assert.isUndefined(packageJsonInfo);
+
+            host.writeFile(packageJson.path, packageJson.content);
+            project.getPackageJsonsVisibleToFile("/src/whatever/blah.ts" as Path);
+            const packageJsonInfo2 = project.packageJsonCache.getInDirectory("/" as Path)!;
+            assert.ok(packageJsonInfo2);
+            assert.ok(packageJsonInfo2.dependencies);
+            assert.ok(packageJsonInfo2.devDependencies);
+            assert.ok(packageJsonInfo2.peerDependencies);
+            assert.ok(packageJsonInfo2.optionalDependencies);
+        });
     });
 
     function setup(files: readonly File[] = [tsConfig, packageJson]) {