fix: update instrument, account for lack of arrow expression (#119) (#…

…125)
istanbuljs · Feb 13, 2018 · 0968206 · 0968206
1 parent 968152e
commit 0968206
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Showing 2 changed files with 46 additions and 2 deletions.
diff --git a/packages/istanbul-lib-instrument/src/visitor.js b/packages/istanbul-lib-instrument/src/visitor.js
@@ -343,9 +343,11 @@ function parenthesizedExpressionProp(prop) {
 function convertArrowExpression(path) {
     const n = path.node;
     const T = this.types;
-    if (n.expression) {
+    if (!T.isBlockStatement(n.body)) {
         const bloc = n.body.loc;
-        n.expression = false;
+        if (n.expression === true) {
+          n.expression = false;
+        }
         n.body = T.blockStatement([
             T.returnStatement(
                 n.body

diff --git a/packages/istanbul-lib-instrument/test/specs/arrow-fn.yaml b/packages/istanbul-lib-instrument/test/specs/arrow-fn.yaml
@@ -19,6 +19,27 @@ tests:
     statements: {'0': 1, '1': 1, '2': 0}
     functions: {'0': 0}
 
+---
+name: es6 arrow function expression - multiple args
+guard: isArrowFnAvailable
+code: |
+  var input = args
+  output = input.reduce((memo, item) => memo + item, 0)
+tests:
+  - name: function called
+    args: [1, 2, 3, 4]
+    out: 10
+    lines: {'1': 1, '2': 4}
+    statements: {'0': 1, '1': 1, '2': 4}
+    functions: {'0': 4}
+
+  - name: function not called
+    args: []
+    out: 0
+    lines: {'1': 1, '2': 1}
+    statements: {'0': 1, '1': 1, '2': 0}
+    functions: {'0': 0}
+
 ---
 name:  es6 arrow function block
 guard: isArrowFnAvailable
@@ -40,6 +61,27 @@ tests:
     statements: {'0': 1, '1': 1, '2': 0}
     functions: {'0': 0}
 
+---
+name: es6 arrow function block - multiple args
+guard: isArrowFnAvailable
+code: |
+  var input = args
+  output = input.reduce((memo, item) => { return memo + item }, 0)
+tests:
+  - name: function called
+    args: [1, 2, 3, 4]
+    out: 10
+    lines: {'1': 1, '2': 4}
+    statements: {'0': 1, '1': 1, '2': 4}
+    functions: {'0': 4}
+
+  - name: function not called
+    args: []
+    out: 0
+    lines: {'1': 1, '2': 1}
+    statements: {'0': 1, '1': 1, '2': 0}
+    functions: {'0': 0}
+
 ---
 name: complex arrow fn
 guard: isArrowFnAvailable