Fixed #1418: missing whitespace when stringifying an expression conta…

…ining "not"

HISTORY.md

@@ -3,6 +3,8 @@
 # Not yet published, version 5.6.0
 
 - Upgrade decimal.js to v10.1.0 (#1421).
+- Fixed #1418: missing whitespace when stringifying an expression
+  containing "not".
 
 
 # 2019-02-20, version 5.5.0

src/expression/node/OperatorNode.js

@@ -370,10 +370,13 @@ function factory (type, config, load, typed) {
         operand = '(' + operand + ')'
       }
 
+      // for example for "not", we want a space between operand and argument
+      const opIsNamed = /[a-zA-Z]+/.test(this.op)
+
       if (assoc === 'right') { // prefix operator
-        return this.op + operand
+        return this.op + (opIsNamed ? ' ' : '') + operand
       } else if (assoc === 'left') { // postfix
-        return operand + this.op
+        return operand + (opIsNamed ? ' ' : '') + this.op
       }
 
       // fall back to postfix

test/expression/parse.test.js

@@ -1949,6 +1949,17 @@ describe('parse', function () {
       assert.strictEqual(parse('1/2a').toString(), '1 / 2 a')
     })
 
+    it('should correctly stringify named operators', function () {
+      assert.strictEqual(parse('7 mod 3').toString(), '7 mod 3')
+      assert.strictEqual(parse('5 inch to cm').toString(), '5 inch to cm')
+      assert.strictEqual(parse('5 inch in cm').toString(), '5 inch in cm')
+      assert.strictEqual(parse('false and true').toString(), 'false and true')
+      assert.strictEqual(parse('false xor true').toString(), 'false xor true')
+      assert.strictEqual(parse('false or true').toString(), 'false or true')
+      assert.strictEqual(parse('not true').toString(), 'not true')
+      assert.strictEqual(parse('5!').toString(), '5!')
+    })
+
     it('should correctly stringify an index with dot notation', function () {
       assert.strictEqual(parse('A[2]').toString(), 'A[2]')
       assert.strictEqual(parse('a["b"]').toString(), 'a["b"]')