fix(autofix): Prevent invalid delete expressions

Check for usage of "delete" keyword with the module export, which is not
fixable as only an identifier would remain after the autofix, which
would not be valid.

Fixes: #668

Author: matz3

src/linter/ui5Types/fixHints/GlobalsFixHintsGenerator.ts

@@ -32,6 +32,15 @@ export default class GlobalsFixHintsGenerator {
 			return undefined;
 		}
 
+		// Check for usage of "delete" keyword with the module export, which is not fixable
+		// as only an identifier would remain after the autofix, which would not be valid.
+		if (
+			ts.isDeleteExpression(propertyAccessNode.parent) &&
+			propertyAccessNode.parent.expression === propertyAccessNode
+		) {
+			return undefined;
+		}
+
 		// Check whether the access is conditional / probing / lazy
 		fixHints.conditional = isConditionalAccess(propertyAccessNode);
 

test/fixtures/autofix/GlobalsConditionalAccess.js

@@ -27,7 +27,7 @@ sap.ui.define([], function() {
 		console.log("Button prototype has someMethod");
 	}
 
-	// // Should be replaced, as there is no lazy dependency to Button in this module
+	// Should be replaced, as there is no lazy dependency to Button in this module
 	const oButton = new sap.m.Button();
 
 });

test/fixtures/autofix/GlobalsNotFixable.js

@@ -10,4 +10,10 @@ sap.ui.define([], function() {
 		}
 	};
 
+	// Delete can't be fixed in case the module export is deleted
+	delete sap.ushell.Container;
+
+	 // Deleting an inner property of a global module access can be fixed
+	delete sap.ushell.Container.getService;
+
 });

test/lib/autofix/snapshots/autofix.fixtures.ts.md

@@ -122,7 +122,7 @@ Generated by [AVA](https://avajs.dev).
     		console.log("Button prototype has someMethod");␊
     	}␊
     ␊
-    	// // Should be replaced, as there is no lazy dependency to Button in this module␊
+    	// Should be replaced, as there is no lazy dependency to Button in this module␊
     	const oButton = new Button();␊
     ␊
     });␊
@@ -2158,7 +2158,7 @@ Generated by [AVA](https://avajs.dev).
     [
       {
         coverageInfo: [],
-        errorCount: 2,
+        errorCount: 3,
         fatalErrorCount: 0,
         filePath: 'GlobalsNotFixable.js',
         messages: [
@@ -2178,11 +2178,42 @@ Generated by [AVA](https://avajs.dev).
             ruleId: 'no-globals',
             severity: 2,
           },
+          {
+            column: 9,
+            line: 14,
+            message: 'Access of global variable \'sap\' (sap.ushell.Container)',
+            messageDetails: 'Do not use global variables to access UI5 modules or APIs. See Best Practices for Developers (https://ui5.sap.com/#/topic/28fcd55b04654977b63dacbee0552712)',
+            ruleId: 'no-globals',
+            severity: 2,
+          },
         ],
         warningCount: 0,
       },
     ]
 
+> AutofixResult: /GlobalsNotFixable.js
+
+    `// Assignments to global variables should not be fixed/replaced␊
+    sap.ui.define(["sap/ushell/Container"], function(Container) {␊
+    ␊
+    	// Declaring globals might appear in tests␊
+    	window.sap.ushell = {};␊
+    	// Assignments can be with or without window prefix␊
+    	sap.ushell.Container = {␊
+    		getService: function() {␊
+    			return {};␊
+    		}␊
+    	};␊
+    ␊
+    	// Delete can't be fixed in case the module export is deleted␊
+    	delete sap.ushell.Container;␊
+    ␊
+    	 // Deleting an inner property of a global module access can be fixed␊
+    	delete Container.getService;␊
+    ␊
+    });␊
+    `
+
 ## General: GlobalsOutsideDefine.js
 
 > Snapshot 1