Fix issue with no-semi style

sindresorhus · Dec 14, 2020 · d9a5d71 · d9a5d71
1 parent 1d85f4f
commit d9a5d71
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Showing 4 changed files with 71 additions and 1 deletion.
diff --git a/rules/no-lonely-if.js b/rules/no-lonely-if.js
@@ -52,7 +52,19 @@ const create = context => {
 					yield fixer.replaceText(outer.test, `${getTestNodeText(outer.test)} && ${getTestNodeText(inner.test)}`);
 
 					// Replace `consequent`
-					yield fixer.replaceText(outer.consequent, getText(inner.consequent));
+					const {consequent} = inner;
+					let consequentText = getText(consequent);
+					// If the `if` statement has no block, and is not followed by a semicolon,
+					// make sure that fixing the issue would not change semantics due to ASI.
+					// Similar logic https://github.com/eslint/eslint/blob/2124e1b5dad30a905dc26bde9da472bf622d3f50/lib/rules/no-lonely-if.js#L61-L77
+					if (consequent.type !== 'BlockStatement' && !consequentText.endsWith(';')) {
+						const nextToken = sourceCode.getTokenAfter(outer);
+						if (/^[([/+`-]/u.test(nextToken.value)) {
+							consequentText += ';';
+						}
+					}
+
+					yield fixer.replaceText(outer.consequent, consequentText);
 				}
 			});
 		}

diff --git a/test/no-lonely-if.js b/test/no-lonely-if.js
@@ -111,5 +111,17 @@ test.visualize([
 			}
 			/* will remove */
 		}
+	`,
+	// Semicolon
+	outdent`
+		if (a) {
+			if (b) foo()
+		}
+		[].forEach(bar)
+	`,
+	outdent`
+		if (a)
+			if (b) foo()
+		;[].forEach(bar)
 	`
 ]);
diff --git a/test/snapshots/no-lonely-if.js.md b/test/snapshots/no-lonely-if.js.md
@@ -429,3 +429,49 @@ Generated by [AVA](https://avajs.dev).
       17 | 	/* will remove */␊
       18 | }␊
     `
+
+## no-lonely-if - #11
+
+> Snapshot 1
+
+    `␊
+    Input:␊
+      1 | if (a) {␊
+      2 | 	if (b) foo()␊
+      3 | }␊
+      4 | [].forEach(bar)␊
+    ␊
+    Output:␊
+      1 | if (a && b) foo();␊
+      2 | [].forEach(bar)␊
+    ␊
+    Error 1/1:␊
+      1 | if (a) {␊
+    > 2 | 	if (b) foo()␊
+        | 	^^^^^^^^^^^^ Unexpected `if` as the only statement in a `if` block without `else`.␊
+      3 | }␊
+      4 | [].forEach(bar)␊
+    `
+
+## no-lonely-if - #12
+
+> Snapshot 1
+
+    `␊
+    Input:␊
+      1 | if (a)␊
+      2 | 	if (b) foo()␊
+      3 | ;[].forEach(bar)␊
+    ␊
+    Output:␊
+      1 | if (a && b)␊
+      2 | 	foo()␊
+      3 | ;[].forEach(bar)␊
+    ␊
+    Error 1/1:␊
+      1 | if (a)␊
+    > 2 | 	if (b) foo()␊
+        | 	^^^^^^^^^^^^␊
+    > 3 | ;[].forEach(bar)␊
+        | ^^ Unexpected `if` as the only statement in a `if` block without `else`.␊
+    `
diff --git a/test/snapshots/no-lonely-if.js.snap b/test/snapshots/no-lonely-if.js.snap