assert: multiple improvements

1) Switched + / - and red / green in diffs. It seems like that style
   is more natural to most people.

2) Short primitives do not use the diff anymore. Especially short
   numbers can be read well like 1 !== 2. Cases that can not be
   displayed like that (e.g., -0 and +0) use the regular diff output.

3) Improved error descriptions. It was not always clear what the
   messages stood for. That should now be resolved.

4) Added a position indicator for single lines in case a tty is used
   and the line is shorter than the visual columns.

5) Color detection is now done by checking stderr instead of stdout.

PR-URL: https://github.com/nodejs/node/pull/21628
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>

1 files changed, 36 insertions, 34 deletions

diff --git a/test/parallel/test-assert-deep.js b/test/parallel/test-assert-deep.js
index 538f4bef49..4536b6d535 100644
--- a/test/parallel/test-assert-deep.js
+++ b/test/parallel/test-assert-deep.js
@@ -4,8 +4,8 @@ const common = require('../common');
 const assert = require('assert');
 const util = require('util');
 const { AssertionError } = assert;
-const defaultMsgStart = 'Input A expected to strictly deep-equal input B:\n' +
-                        '+ expected - actual';
+const defaultMsgStart = 'Expected inputs to be strictly deep-equal:\n';
+const defaultMsgStartFull = `${defaultMsgStart}+ actual - expected`;
 
 // Disable colored output to prevent color codes from breaking assertion
 // message comparisons. This should only be an issue when process.stdout
@@ -44,9 +44,9 @@ assert.throws(
   () => assert.deepStrictEqual(arr, buf),
   {
     code: 'ERR_ASSERTION',
-    message: `${defaultMsgStart} ... Lines skipped\n\n` +
-             '- Uint8Array [\n' +
-             '+ Buffer [Uint8Array] [\n    120,\n...\n    10\n  ]'
+    message: `${defaultMsgStartFull} ... Lines skipped\n\n` +
+             '+ Uint8Array [\n' +
+             '- Buffer [Uint8Array] [\n    120,\n...\n    10\n  ]'
   }
 );
 assert.deepEqual(arr, buf);
@@ -59,9 +59,9 @@ assert.deepEqual(arr, buf);
     () => assert.deepStrictEqual(buf2, buf),
     {
       code: 'ERR_ASSERTION',
-      message: `${defaultMsgStart}\n\n` +
+      message: `${defaultMsgStartFull}\n\n` +
                '  Buffer [Uint8Array] [\n    120,\n    121,\n    122,\n' +
-               '-   10,\n-   prop: 1\n+   10\n  ]'
+               '+   10,\n+   prop: 1\n-   10\n  ]'
     }
   );
   assert.deepEqual(buf2, buf);
@@ -74,9 +74,9 @@ assert.deepEqual(arr, buf);
     () => assert.deepStrictEqual(arr, arr2),
     {
       code: 'ERR_ASSERTION',
-      message: `${defaultMsgStart}\n\n` +
+      message: `${defaultMsgStartFull}\n\n` +
                '  Uint8Array [\n    120,\n    121,\n    122,\n' +
-               '-   10\n+   10,\n+   prop: 5\n  ]'
+               '+   10\n-   10,\n-   prop: 5\n  ]'
     }
   );
   assert.deepEqual(arr, arr2);
@@ -101,18 +101,18 @@ assert.throws(
   () => assert.deepStrictEqual(date, date2),
   {
     code: 'ERR_ASSERTION',
-    message: `${defaultMsgStart}\n\n` +
-             '- 2016-01-01T00:00:00.000Z\n+ 2016-01-01T00:00:00.000Z {\n' +
-             "+   '0': '1'\n+ }"
+    message: `${defaultMsgStartFull}\n\n` +
+             '+ 2016-01-01T00:00:00.000Z\n- 2016-01-01T00:00:00.000Z {\n' +
+             "-   '0': '1'\n- }"
   }
 );
 assert.throws(
   () => assert.deepStrictEqual(date2, date),
   {
     code: 'ERR_ASSERTION',
-    message: `${defaultMsgStart}\n\n` +
-             '- 2016-01-01T00:00:00.000Z {\n' +
-             "-   '0': '1'\n- }\n+ 2016-01-01T00:00:00.000Z"
+    message: `${defaultMsgStartFull}\n\n` +
+             '+ 2016-01-01T00:00:00.000Z {\n' +
+             "+   '0': '1'\n+ }\n- 2016-01-01T00:00:00.000Z"
   }
 );
 
@@ -133,8 +133,8 @@ assert.throws(
   () => assert.deepStrictEqual(re1, re2),
   {
     code: 'ERR_ASSERTION',
-    message: `${defaultMsgStart}\n\n` +
-             "- /test/\n+ /test/ {\n+   '0': '1'\n+ }"
+    message: `${defaultMsgStartFull}\n\n` +
+             "+ /test/\n- /test/ {\n-   '0': '1'\n- }"
   }
 );
 
@@ -498,8 +498,8 @@ assertOnlyDeepEqual(
     () => assert.deepStrictEqual(map1, map2),
     {
       code: 'ERR_ASSERTION',
-      message: `${defaultMsgStart}\n\n` +
-               "  Map {\n-   1 => 1\n+   1 => '1'\n  }"
+      message: `${defaultMsgStartFull}\n\n` +
+               "  Map {\n+   1 => 1\n-   1 => '1'\n  }"
     }
   );
 }
@@ -750,7 +750,7 @@ assert.throws(
   () => assert.notDeepStrictEqual(new Date(2000, 3, 14), new Date(2000, 3, 14)),
   {
     name: 'AssertionError [ERR_ASSERTION]',
-    message: 'Identical input passed to notDeepStrictEqual: ' +
+    message: 'Expected "actual" not to be strictly deep-equal to: ' +
              util.inspect(new Date(2000, 3, 14))
   }
 );
@@ -767,35 +767,35 @@ assert.throws(
   {
     code: 'ERR_ASSERTION',
     name: 'AssertionError [ERR_ASSERTION]',
-    message: `${defaultMsgStart}\n\n- /ab/\n+ /a/`
+    message: `${defaultMsgStartFull}\n\n+ /ab/\n- /a/`
   });
 assert.throws(
   () => assert.deepStrictEqual(/a/g, /a/),
   {
     code: 'ERR_ASSERTION',
     name: 'AssertionError [ERR_ASSERTION]',
-    message: `${defaultMsgStart}\n\n- /a/g\n+ /a/`
+    message: `${defaultMsgStartFull}\n\n+ /a/g\n- /a/`
   });
 assert.throws(
   () => assert.deepStrictEqual(/a/i, /a/),
   {
     code: 'ERR_ASSERTION',
     name: 'AssertionError [ERR_ASSERTION]',
-    message: `${defaultMsgStart}\n\n- /a/i\n+ /a/`
+    message: `${defaultMsgStartFull}\n\n+ /a/i\n- /a/`
   });
 assert.throws(
   () => assert.deepStrictEqual(/a/m, /a/),
   {
     code: 'ERR_ASSERTION',
     name: 'AssertionError [ERR_ASSERTION]',
-    message: `${defaultMsgStart}\n\n- /a/m\n+ /a/`
+    message: `${defaultMsgStartFull}\n\n+ /a/m\n- /a/`
   });
 assert.throws(
   () => assert.deepStrictEqual(/a/igm, /a/im),
   {
     code: 'ERR_ASSERTION',
     name: 'AssertionError [ERR_ASSERTION]',
-    message: `${defaultMsgStart}\n\n- /a/gim\n+ /a/im`
+    message: `${defaultMsgStartFull}\n\n+ /a/gim\n- /a/im\n     ^`
   });
 
 {
@@ -806,12 +806,12 @@ assert.throws(
 
 assert.throws(
   () => assert.deepStrictEqual(4, '4'),
-  { message: `${defaultMsgStart}\n\n- 4\n+ '4'` }
+  { message: `${defaultMsgStart}\n4 !== '4'\n` }
 );
 
 assert.throws(
   () => assert.deepStrictEqual(true, 1),
-  { message: `${defaultMsgStart}\n\n- true\n+ 1` }
+  { message: `${defaultMsgStart}\ntrue !== 1\n` }
 );
 
 // Having the same number of owned properties && the same set of keys.
@@ -821,21 +821,23 @@ assert.throws(() => assert.deepStrictEqual([4], ['4']),
               {
                 code: 'ERR_ASSERTION',
                 name: 'AssertionError [ERR_ASSERTION]',
-                message: `${defaultMsgStart}\n\n  [\n-   4\n+   '4'\n  ]`
+                message: `${defaultMsgStartFull}\n\n  [\n+   4\n-   '4'\n  ]`
               });
 assert.throws(
   () => assert.deepStrictEqual({ a: 4 }, { a: 4, b: true }),
   {
     code: 'ERR_ASSERTION',
     name: 'AssertionError [ERR_ASSERTION]',
-    message: `${defaultMsgStart}\n\n  {\n-   a: 4\n+   a: 4,\n+   b: true\n  }`
+    message: `${defaultMsgStartFull}\n\n  ` +
+             '{\n+   a: 4\n-   a: 4,\n-   b: true\n  }'
   });
 assert.throws(
   () => assert.deepStrictEqual(['a'], { 0: 'a' }),
   {
     code: 'ERR_ASSERTION',
     name: 'AssertionError [ERR_ASSERTION]',
-    message: `${defaultMsgStart}\n\n- [\n-   'a'\n- ]\n+ {\n+   '0': 'a'\n+ }`
+    message: `${defaultMsgStartFull}\n\n` +
+             "+ [\n+   'a'\n+ ]\n- {\n-   '0': 'a'\n- }"
   });
 
 /* eslint-enable */
@@ -906,8 +908,8 @@ assert.throws(() => assert.deepStrictEqual(new Boolean(true), {}),
   assert.throws(
     () => assert.deepStrictEqual(a, b),
     {
-      message: `${defaultMsgStart}\n\n` +
-               '  [TypeError: foo] {\n-   foo: \'bar\'\n+   foo: \'baz\'\n  }'
+      message: `${defaultMsgStartFull}\n\n` +
+               '  [TypeError: foo] {\n+   foo: \'bar\'\n-   foo: \'baz\'\n  }'
     }
   );
 }
@@ -922,8 +924,8 @@ assert.throws(() => assert.deepStrictEqual(new Boolean(true), {}),
   util.inspect.defaultOptions = { showProxy: true };
   assert.throws(
     () => assert.deepStrictEqual(arrProxy, [1, 2, 3]),
-    { message: `${defaultMsgStart}\n\n` +
-               '  [\n    1,\n-   2\n+   2,\n+   3\n  ]' }
+    { message: `${defaultMsgStartFull}\n\n` +
+               '  [\n    1,\n+   2\n-   2,\n-   3\n  ]' }
   );
   util.inspect.defaultOptions = tmp;
 }