Added support for explicit case statement fall through

johnantoni · Feb 24, 2011 · 4a72da1 · 4a72da1
1 parent d193b1c
commit 4a72da1
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Showing 2 changed files with 36 additions and 3 deletions.
diff --git a/jshint.js b/jshint.js
@@ -1012,6 +1012,8 @@ var JSHINT = (function () {
         qx = /[^a-zA-Z0-9+\-_\/ ]/,
 // query characters for ids
         dx = /[\[\]\/\\"'*<>.&:(){}+=#]/,
+// catches /* falls through */ comments
+        ft = /^\s*\/\*\s*falls\sthrough\s*\*\/\s*$/,
 
         rx = {
             outer: hx,
@@ -5148,9 +5150,14 @@ loop:   for (;;) {
                 case 'throw':
                     break;
                 default:
-                    warning(
-                        "Expected a 'break' statement before 'case'.",
-                        token);
+                    // You can tell JSHint that you don't use break intentionally by
+                    // adding a comment /* falls through */ on a line just before
+                    // the next `case`.
+                    if (!ft.test(lines[nexttoken.line - 2])) {
+                        warning(
+                            "Expected a 'break' statement before 'case'.",
+                            token);
+                    }
                 }
                 indentation(-option.indent);
                 advance('case');

diff --git a/tests/jshint.js b/tests/jshint.js
@@ -184,6 +184,32 @@ describe("Control statements", function () {
         expect(JSHINT(eqnull, { boss: true })).toEqual(true);
         expect(JSHINT(nulleq, { boss: true })).toEqual(true);
     });
+
+    it("should not implicit allow case statement fall through by default", function () {
+        var code = [
+            "switch(foo) {"
+          , "case 1:"
+          ,     "doSmth();"
+          , "case 2:"
+          ,     "doSmth();"
+          , "}"
+        ];
+
+        expect(JSHINT(code)).toEqual(false);
+    });
+
+    it("should allow explicit case statement fall through", function () {
+        var code = [
+            "switch(foo) {"
+          , "case 1:"
+          ,     "doSmth();"
+          ,     "/* falls through */"
+          , "case 2:"
+          ,     "doSmth();"
+          , "}"
+        ];
+        expect(JSHINT(code)).toEqual(true);
+    });
 });
 
 describe("Globals", function () {