Cleanup relative_test (flutter#65)

Define individual groups and tests for most cases
Makes debugging individual failures much easier

Author: kevmoo

test/relative_test.dart

@@ -4,82 +4,103 @@
 //
 // Test "relative" on all styles of path.Context, on all platforms.
 
-import 'package:test/test.dart';
 import 'package:path/path.dart' as path;
+import 'package:test/test.dart';
 
 import 'utils.dart';
 
 void main() {
-  test('test relative', () {
-    relativeTest(path.Context(style: path.Style.posix, current: '.'), '/');
-    relativeTest(path.Context(style: path.Style.posix, current: '/'), '/');
-    relativeTest(
-        path.Context(style: path.Style.windows, current: r'd:\'), r'c:\');
-    relativeTest(path.Context(style: path.Style.windows, current: '.'), r'c:\');
-    relativeTest(path.Context(style: path.Style.url, current: 'file:///'),
-        'http://myserver/');
-    relativeTest(
-        path.Context(style: path.Style.url, current: '.'), 'http://myserver/');
-    relativeTest(path.Context(style: path.Style.url, current: 'file:///'), '/');
-    relativeTest(path.Context(style: path.Style.url, current: '.'), '/');
-  });
+  relativeTest(path.Context(style: path.Style.posix, current: '.'), '/');
+  relativeTest(path.Context(style: path.Style.posix, current: '/'), '/');
+  relativeTest(
+    path.Context(style: path.Style.windows, current: r'd:\'),
+    r'c:\',
+  );
+  relativeTest(path.Context(style: path.Style.windows, current: '.'), r'c:\');
+  relativeTest(
+    path.Context(style: path.Style.url, current: 'file:///'),
+    'http://myserver/',
+  );
+  relativeTest(
+    path.Context(style: path.Style.url, current: '.'),
+    'http://myserver/',
+  );
+  relativeTest(path.Context(style: path.Style.url, current: 'file:///'), '/');
+  relativeTest(path.Context(style: path.Style.url, current: '.'), '/');
 }
 
 void relativeTest(path.Context context, String prefix) {
-  final isRelative = context.current == '.';
   // Cases where the arguments are absolute paths.
   void expectRelative(String result, String pathArg, String fromArg) {
-    expect(context.relative(pathArg, from: fromArg), context.normalize(result));
+    test('relative $pathArg from $fromArg', () {
+      expect(
+        context.relative(pathArg, from: fromArg),
+        context.normalize(result),
+      );
+    });
   }
 
-  expectRelative('c/d', '${prefix}a/b/c/d', '${prefix}a/b');
-  expectRelative('c/d', '${prefix}a/b/c/d', '${prefix}a/b/');
-  expectRelative('.', '${prefix}a', '${prefix}a');
-  // Trailing slashes in the inputs have no effect.
-  expectRelative('../../z/x/y', '${prefix}a/b/z/x/y', '${prefix}a/b/c/d/');
-  expectRelative('../../z/x/y', '${prefix}a/b/z/x/y', '${prefix}a/b/c/d');
-  expectRelative('../../z/x/y', '${prefix}a/b/z/x/y/', '${prefix}a/b/c/d');
-  expectRelative('../../../z/x/y', '${prefix}z/x/y', '${prefix}a/b/c');
-  expectRelative('../../../z/x/y', '${prefix}z/x/y', '${prefix}a/b/c/');
+  group('${context.style}', () {
+    expectRelative('c/d', '${prefix}a/b/c/d', '${prefix}a/b');
+    expectRelative('c/d', '${prefix}a/b/c/d', '${prefix}a/b/');
+    expectRelative('.', '${prefix}a', '${prefix}a');
+    // Trailing slashes in the inputs have no effect.
+    expectRelative('../../z/x/y', '${prefix}a/b/z/x/y', '${prefix}a/b/c/d/');
+    expectRelative('../../z/x/y', '${prefix}a/b/z/x/y', '${prefix}a/b/c/d');
+    expectRelative('../../z/x/y', '${prefix}a/b/z/x/y/', '${prefix}a/b/c/d');
+    expectRelative('../../../z/x/y', '${prefix}z/x/y', '${prefix}a/b/c');
+    expectRelative('../../../z/x/y', '${prefix}z/x/y', '${prefix}a/b/c/');
 
-  // Cases where the arguments are relative paths.
-  expectRelative('c/d', 'a/b/c/d', 'a/b');
-  expectRelative('.', 'a/b/c', 'a/b/c');
-  expectRelative('.', 'a/d/../b/c', 'a/b/c/');
-  expectRelative('.', '', '');
-  expectRelative('.', '.', '');
-  expectRelative('.', '', '.');
-  expectRelative('.', '.', '.');
-  expectRelative('.', '..', '..');
-  if (isRelative) expectRelative('..', '..', '.');
-  expectRelative('a', 'a', '');
-  expectRelative('a', 'a', '.');
-  expectRelative('..', '.', 'a');
-  expectRelative('.', 'a/b/f/../c', 'a/e/../b/c');
-  expectRelative('d', 'a/b/f/../c/d', 'a/e/../b/c');
-  expectRelative('..', 'a/b/f/../c', 'a/e/../b/c/e/');
-  expectRelative('../..', '', 'a/b/');
-  if (isRelative) expectRelative('../../..', '..', 'a/b/');
-  expectRelative('../b/c/d', 'b/c/d/', 'a/');
-  expectRelative('../a/b/c', 'x/y/a//b/./f/../c', 'x//y/z');
+    // Cases where the arguments are relative paths.
+    expectRelative('c/d', 'a/b/c/d', 'a/b');
+    expectRelative('.', 'a/b/c', 'a/b/c');
+    expectRelative('.', 'a/d/../b/c', 'a/b/c/');
+    expectRelative('.', '', '');
+    expectRelative('.', '.', '');
+    expectRelative('.', '', '.');
+    expectRelative('.', '.', '.');
+    expectRelative('.', '..', '..');
+    expectRelative('a', 'a', '');
+    expectRelative('a', 'a', '.');
+    expectRelative('..', '.', 'a');
+    expectRelative('.', 'a/b/f/../c', 'a/e/../b/c');
+    expectRelative('d', 'a/b/f/../c/d', 'a/e/../b/c');
+    expectRelative('..', 'a/b/f/../c', 'a/e/../b/c/e/');
+    expectRelative('../..', '', 'a/b/');
+    expectRelative('../b/c/d', 'b/c/d/', 'a/');
+    expectRelative('../a/b/c', 'x/y/a//b/./f/../c', 'x//y/z');
 
-  // Case where from is an exact substring of path.
-  expectRelative('a/b', '${prefix}x/y//a/b', '${prefix}x/y/');
-  expectRelative('a/b', 'x/y//a/b', 'x/y/');
-  expectRelative('../ya/b', '${prefix}x/ya/b', '${prefix}x/y');
-  expectRelative('../ya/b', 'x/ya/b', 'x/y');
-  expectRelative('../b', 'x/y/../b', 'x/y/.');
-  expectRelative('a/b/c', 'x/y/a//b/./f/../c', 'x/y');
-  expectRelative('.', '${prefix}x/y//', '${prefix}x/y/');
-  expectRelative('.', '${prefix}x/y/', '${prefix}x/y');
+    // Case where from is an exact substring of path.
+    expectRelative('a/b', '${prefix}x/y//a/b', '${prefix}x/y/');
+    expectRelative('a/b', 'x/y//a/b', 'x/y/');
+    expectRelative('../ya/b', '${prefix}x/ya/b', '${prefix}x/y');
+    expectRelative('../ya/b', 'x/ya/b', 'x/y');
+    expectRelative('../b', 'x/y/../b', 'x/y/.');
+    expectRelative('a/b/c', 'x/y/a//b/./f/../c', 'x/y');
+    expectRelative('.', '${prefix}x/y//', '${prefix}x/y/');
+    expectRelative('.', '${prefix}x/y/', '${prefix}x/y');
 
-  // Should always throw - no relative path can be constructed.
-  if (isRelative) {
-    expect(() => context.relative('.', from: '..'), throwsPathException);
-    expect(() => context.relative('a/b', from: '../../d'), throwsPathException);
-    expect(() => context.relative('a/b', from: '${prefix}a/b'),
-        throwsPathException);
-    // An absolute path relative from a relative path returns the absolute path.
-    expectRelative('${prefix}a/b', '${prefix}a/b', 'c/d');
-  }
+    if (context.current == '.') {
+      group('current directory', () {
+        // Should always throw - no relative path can be constructed.
+        test('throws', () {
+          expect(() => context.relative('.', from: '..'), throwsPathException);
+          expect(
+            () => context.relative('a/b', from: '../../d'),
+            throwsPathException,
+          );
+          expect(
+            () => context.relative('a/b', from: '${prefix}a/b'),
+            throwsPathException,
+          );
+        });
+
+        expectRelative('..', '..', '.');
+        expectRelative('../../..', '..', 'a/b/');
+
+        // absolute path relative from a relative path returns the absolute path
+        expectRelative('${prefix}a/b', '${prefix}a/b', 'c/d');
+      });
+    }
+  });
 }