fix nocase matching on case-sensitive filesystems

If the platform indicates that the filesystem is likely case-sensitive
(ie, not darwin or win32), and nocase:true is set, we can't know if
that's indicating that the filesystem _itself_ is case-insensitive, or
if the user simply wants to perform case-insensitive matching.

In the case where it is in fact likely case-sensitive, and `nocase:true`
is set, do _not_ set `nocaseMagicOnly`, because filesystem operations
will not be run case-insensitively.

Fix: #526

Author: isaacs

src/glob.ts

@@ -457,14 +457,21 @@ export class Glob<Opts extends GlobOptions> implements GlobOptions {
     }
     this.nocase = this.scurry.nocase
 
+    // If you do nocase:true on a case-sensitive file system, then
+    // we need to use regexps instead of strings for non-magic
+    // path portions, because statting `aBc` won't return results
+    // for the file `AbC` for example.
+    const nocaseMagicOnly =
+      this.platform === 'darwin' || this.platform === 'win32'
+
     const mmo: MinimatchOptions = {
       // default nocase based on platform
       ...opts,
       dot: this.dot,
       matchBase: this.matchBase,
       nobrace: this.nobrace,
       nocase: this.nocase,
-      nocaseMagicOnly: true,
+      nocaseMagicOnly,
       nocomment: true,
       noext: this.noext,
       nonegate: true,

test/nocase-magic-only.ts

@@ -0,0 +1,8 @@
+import t from 'tap'
+import { Glob } from '../dist/cjs/src/index.js'
+
+const darwin = new Glob('x', { nocase: true, platform: 'darwin' })
+const linux = new Glob('x', { nocase: true, platform: 'linux' })
+
+t.type(darwin.patterns[0].pattern(), 'string')
+t.type(linux.patterns[0].pattern(), RegExp)