fix: guard against null deepest identifier node

Author: Belco90

lib/detect-testing-library-utils.ts

@@ -477,6 +477,10 @@ export function detectTestingLibraryUtils<
     const isRenderVariableDeclarator: IsRenderVariableDeclaratorFn = (node) => {
       const initIdentifierNode = getDeepestIdentifierNode(node.init);
 
+      if (!initIdentifierNode) {
+        return false;
+      }
+
       return isRenderUtil(initIdentifierNode);
     };
 

lib/rules/no-await-sync-events.ts

@@ -42,6 +42,10 @@ export default createTestingLibraryRule<Options, MessageIds>({
       'AwaitExpression > CallExpression'(node: TSESTree.CallExpression) {
         const simulateEventFunctionIdentifier = getDeepestIdentifierNode(node);
 
+        if (!simulateEventFunctionIdentifier) {
+          return;
+        }
+
         const isSimulateEventMethod =
           helpers.isUserEventMethod(simulateEventFunctionIdentifier) ||
           helpers.isFireEventMethod(simulateEventFunctionIdentifier);

lib/rules/no-container.ts

@@ -84,6 +84,11 @@ export default createTestingLibraryRule<Options, MessageIds>({
     return {
       CallExpression(node) {
         const callExpressionIdentifier = getDeepestIdentifierNode(node);
+
+        if (!callExpressionIdentifier) {
+          return;
+        }
+
         if (helpers.isRenderUtil(callExpressionIdentifier)) {
           detectRenderWrapper(callExpressionIdentifier);
         }
@@ -103,6 +108,10 @@ export default createTestingLibraryRule<Options, MessageIds>({
       VariableDeclarator(node) {
         const initIdentifierNode = getDeepestIdentifierNode(node.init);
 
+        if (!initIdentifierNode) {
+          return;
+        }
+
         const isRenderWrapperVariableDeclarator = initIdentifierNode
           ? renderWrapperNames.includes(initIdentifierNode.name)
           : false;

lib/rules/no-debug.ts

@@ -48,6 +48,10 @@ export default createTestingLibraryRule<Options, MessageIds>({
       VariableDeclarator(node) {
         const initIdentifierNode = getDeepestIdentifierNode(node.init);
 
+        if (!initIdentifierNode) {
+          return;
+        }
+
         const isRenderWrapperVariableDeclarator = initIdentifierNode
           ? renderWrapperNames.includes(initIdentifierNode.name)
           : false;
@@ -68,9 +72,11 @@ export default createTestingLibraryRule<Options, MessageIds>({
               ASTUtils.isIdentifier(property.key) &&
               property.key.name === 'debug'
             ) {
-              suspiciousDebugVariableNames.push(
-                getDeepestIdentifierNode(property.value).name
-              );
+              const identifierNode = getDeepestIdentifierNode(property.value);
+
+              if (identifierNode) {
+                suspiciousDebugVariableNames.push(identifierNode.name);
+              }
             }
           }
         }
@@ -83,6 +89,11 @@ export default createTestingLibraryRule<Options, MessageIds>({
       },
       CallExpression(node) {
         const callExpressionIdentifier = getDeepestIdentifierNode(node);
+
+        if (!callExpressionIdentifier) {
+          return;
+        }
+
         if (helpers.isRenderUtil(callExpressionIdentifier)) {
           detectRenderWrapper(callExpressionIdentifier);
         }

lib/rules/no-promise-in-fire-event.ts

@@ -52,6 +52,10 @@ export default createTestingLibraryRule<Options, MessageIds>({
       if (isCallExpression(node)) {
         const domElementIdentifier = getDeepestIdentifierNode(node);
 
+        if (!domElementIdentifier) {
+          return;
+        }
+
         if (
           helpers.isAsyncQuery(domElementIdentifier) ||
           isPromiseIdentifier(domElementIdentifier)

lib/rules/no-render-in-setup.ts

@@ -84,6 +84,11 @@ export default createTestingLibraryRule<Options, MessageIds>({
           (hook) => hook !== allowTestingFrameworkSetupHook
         );
         const callExpressionIdentifier = getDeepestIdentifierNode(node);
+
+        if (!callExpressionIdentifier) {
+          return;
+        }
+
         const isRenderIdentifier = helpers.isRenderUtil(
           callExpressionIdentifier
         );

lib/rules/render-result-naming-convention.ts

@@ -48,6 +48,11 @@ export default createTestingLibraryRule<Options, MessageIds>({
     return {
       CallExpression(node) {
         const callExpressionIdentifier = getDeepestIdentifierNode(node);
+
+        if (!callExpressionIdentifier) {
+          return;
+        }
+
         if (helpers.isRenderUtil(callExpressionIdentifier)) {
           detectRenderWrapper(callExpressionIdentifier);
         }

tests/lib/rules/no-debug.test.ts

@@ -139,6 +139,10 @@ ruleTester.run(RULE_NAME, rule, {
       debug()
       `,
     },
+
+    `// cover edge case for https://github.com/testing-library/eslint-plugin-testing-library/issues/306
+    thing.method.lastCall.args[0]();
+    `,
   ],
 
   invalid: [