support non-error objects and browser error objects

charlierudolph · Nov 27, 2017 · ca21cfd · ca21cfd
1 parent 2e02575
commit ca21cfd
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Showing 2 changed files with 80 additions and 34 deletions.
diff --git a/src/index.js b/src/index.js
@@ -27,13 +27,17 @@ export function format(err, options) {
     message = err.message + ''
   } else if (typeof err.inspect === 'function') {
     message = err.inspect() + ''
-  } else {
+  } else if (typeof err === 'string') {
     message = err
+  } else {
+    message = JSON.stringify(err)
   }
 
   let stack = err.stack || message
   const startOfMessageIndex = stack.indexOf(message)
-  if (startOfMessageIndex !== -1) {
+  if (startOfMessageIndex === -1) {
+    stack = '\n' + stack
+  } else {
     const endOfMessageIndex = startOfMessageIndex + message.length
     message = stack.slice(0, endOfMessageIndex)
     stack = stack.slice(endOfMessageIndex) // remove message from stack

diff --git a/src/index_test.js b/src/index_test.js
@@ -1,4 +1,3 @@
-import {AssertionError} from 'assert'
 import {format} from './'
 
 describe('AssertionErrorFormatter', function() {
@@ -25,35 +24,45 @@ describe('AssertionErrorFormatter', function() {
     describe('with assertion error', function() {
       describe('unified diffs', function() {
         it('should show string diffs', function() {
-          const error = new AssertionError({
+          const error = {
             actual: 'foo',
             expected: 'bar',
-            operator: 'to equal'
-          })
+            message: '\'foo\' to equal \'bar\'',
+            stack: '\'foo\' to equal \'bar\'\n    line1\n    line2\n    line3'
+          }
           expect(format(error, this.options)).to.eql(
-            '<em>AssertionError: \'foo\' to equal \'bar\'</em>\n' +
+            '<em>\'foo\' to equal \'bar\'</em>\n' +
             '    <da>+ expected</da> <dr>- actual</dr>\n' +
             '\n' +
             '    <dr>-foo</dr>\n' +
-            '    <da>+bar</da>\n'
+            '    <da>+bar</da>\n' +
+            '<es>\n' +
+            '    line1\n' +
+            '    line2\n' +
+            '    line3</es>'
           )
         })
 
         it('should show object diffs', function() {
-          const error = new AssertionError({
+          const error = {
             actual: {x: 1, y: 2},
             expected: {x: 1, y: 3},
-            operator: 'to equal'
-          })
+            message: '{ x: 1, y: 2 } to equal { x: 1, y: 3 }',
+            stack: '{ x: 1, y: 2 } to equal { x: 1, y: 3 }\n    line1\n    line2\n    line3'
+          }
           expect(format(error, this.options)).to.eql(
-            '<em>AssertionError: { x: 1, y: 2 } to equal { x: 1, y: 3 }</em>\n' +
+            '<em>{ x: 1, y: 2 } to equal { x: 1, y: 3 }</em>\n' +
             '    <da>+ expected</da> <dr>- actual</dr>\n' +
             '\n' +
             '     {\n' +
             '       "x": 1\n' +
             '    <dr>-  "y": 2</dr>\n' +
             '    <da>+  "y": 3</da>\n' +
-            '     }\n'
+            '     }\n' +
+            '<es>\n' +
+            '    line1\n' +
+            '    line2\n' +
+            '    line3</es>'
           )
         })
       })
@@ -64,50 +73,77 @@ describe('AssertionErrorFormatter', function() {
         })
 
         it('should show string diffs', function() {
-          const error = new AssertionError({
+          const error = {
             actual: 'foo',
             expected: 'bar',
-            operator: 'to equal'
-          })
+            message: '\'foo\' to equal \'bar\'',
+            stack: '\'foo\' to equal \'bar\'\n    line1\n    line2\n    line3'
+          }
           expect(format(error, this.options)).to.eql(
-            '<em>AssertionError: \'foo\' to equal \'bar\'</em>\n' +
+            '<em>\'foo\' to equal \'bar\'</em>\n' +
             '    <dr>actual</dr> <da>expected</da>\n' +
             '\n' +
-            '    <dr>foo</dr><da>bar</da>\n'
+            '    <dr>foo</dr><da>bar</da>\n' +
+            '<es>\n' +
+            '    line1\n' +
+            '    line2\n' +
+            '    line3</es>'
           )
         })
 
         it('should show object diffs', function() {
-          const error = new AssertionError({
+          const error = {
             actual: {x: 1, y: 2},
             expected: {x: 1, y: 3},
-            operator: 'to equal'
-          })
+            message: '{ x: 1, y: 2 } to equal { x: 1, y: 3 }',
+            stack: '{ x: 1, y: 2 } to equal { x: 1, y: 3 }\n    line1\n    line2\n    line3'
+          }
           expect(format(error, this.options)).to.eql(
-            '<em>AssertionError: { x: 1, y: 2 } to equal { x: 1, y: 3 }</em>\n' +
+            '<em>{ x: 1, y: 2 } to equal { x: 1, y: 3 }</em>\n' +
             '    <dr>actual</dr> <da>expected</da>\n' +
             '\n' +
             '    {\n' +
             '      "x": 1\n' +
             '      "y": <dr>2</dr><da>3</da>\n' +
-            '    }\n'
+            '    }\n' +
+            '<es>\n' +
+            '    line1\n' +
+            '    line2\n' +
+            '    line3</es>'
           )
         })
       })
     })
 
     describe('with other error', function() {
-      it('colors the error message', function() {
-        const error = {
-          message: 'abc',
-          stack: 'abc\n    def\n    ghi'
-        }
-        //const error2 = new Error('abc')
-        expect(format(error, this.options)).to.eql(
-          '<em>abc</em><es>\n' +
-          '    def\n' +
-          '    ghi</es>'
-        )
+      describe('message is in the stack', function() {
+        it('returns the stack only', function() {
+          const error = {
+            message: 'abc',
+            stack: 'abc\n    line1\n    line2\n    line3'
+          }
+          expect(format(error, this.options)).to.eql(
+            '<em>abc</em><es>\n' +
+            '    line1\n' +
+            '    line2\n' +
+            '    line3</es>'
+          )
+        })
+      })
+
+      describe('message is not in the stack', function() {
+        it('returns the message and the stack', function() {
+          const error = {
+            message: 'abc',
+            stack: 'line1\nline2\nline3'
+          }
+          expect(format(error, this.options)).to.eql(
+            '<em>abc</em><es>\n' +
+            'line1\n' +
+            'line2\n' +
+            'line3</es>'
+          )
+        })
       })
     })
 
@@ -116,5 +152,11 @@ describe('AssertionErrorFormatter', function() {
         expect(format('abc', this.options)).to.eql('<em>abc</em>')
       })
     })
+
+    describe('with object', function() {
+      it('outputs the json stringified object', function() {
+        expect(format({x: 1, y: 2}, this.options)).to.eql('<em>{"x":1,"y":2}</em>')
+      })
+    })
   })
 })