fix(amazonq): tf scans mapped to wrong language #4975

Problem:
Projects with terraform files fail with `Improperly formed request` error. This
is happening due to `tf` incorrectly mapped to `hcl`.

Solution:
The reverse map lookup function `getLanguageFromFileExtension` is unreliable
because there could be duplicate values. Use `getLanguageContext` instead.

Author: ctlai95

packages/amazonq/.changes/next-release/Bug Fix-7d44c921-beb1-42c5-9a6c-35efc4994d4d.json

@@ -0,0 +1,4 @@
+{
+	"type": "Bug Fix",
+	"description": "Security Scan: Fixes an issue where scans fail for projects with Terraform files"
+}

packages/core/src/codewhisperer/util/runtimeLanguageContext.ts

@@ -180,17 +180,6 @@ export class RuntimeLanguageContext {
         return { language: this.normalizeLanguage(languageId) ?? 'plaintext' }
     }
 
-    /**
-     *
-     * @param fileExtension File extension i.e. py, js, java
-     * @returns The corresponding {@link CodewhispererLanguage} of the file extension
-     */
-    public getLanguageFromFileExtension(fileExtension: string): CodewhispererLanguage | undefined {
-        return [...this.supportedLanguageExtensionMap.entries()].find(
-            ([, extension]) => extension === fileExtension
-        )?.[0]
-    }
-
     /**
      * Mapping the field ProgrammingLanguage of codewhisperer generateRecommendationRequest | listRecommendationRequest to
      * its Codewhisperer runtime language e.g. jsx -> typescript, typescript -> typescript

packages/core/src/codewhisperer/util/zipUtil.ts

@@ -152,10 +152,12 @@ export class ZipUtil {
                 this._totalSize += fileSize
                 this._totalLines += fileContent.split(ZipConstants.newlineRegex).length
 
-                const language = runtimeLanguageContext.getLanguageFromFileExtension(
+                const document = await vscode.workspace.openTextDocument(file.fileUri)
+                const { language } = runtimeLanguageContext.getLanguageContext(
+                    document.languageId,
                     path.extname(file.fileUri.fsPath).slice(1)
                 )
-                if (language) {
+                if (language && language !== 'plaintext') {
                     languageCount.set(language, (languageCount.get(language) || 0) + 1)
                 }
             }