go/analysis/unitchecker: allow dash in file paths

The temporary directory may contain a dash, and the test shouldn't
fail because of that.

Fixes golang/go#31164

Change-Id: I3c0d636771e13fec345e46394fb548e3c4ea4478
Reviewed-on: https://go-review.googlesource.com/c/tools/+/170177
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/go/analysis/unitchecker/unitchecker_test.go b/go/analysis/unitchecker/unitchecker_test.go
index d7e7ee6..4a302ff 100644
--- a/go/analysis/unitchecker/unitchecker_test.go
+++ b/go/analysis/unitchecker/unitchecker_test.go
@@ -78,18 +78,18 @@
 	defer exported.Cleanup()
 
 	const wantA = `# golang.org/fake/a
-([/._a-zA-Z0-9]+[\\/]fake[\\/])?a/a.go:4:11: call of MyFunc123\(...\)
+([/._\-a-zA-Z0-9]+[\\/]fake[\\/])?a/a.go:4:11: call of MyFunc123\(...\)
 `
 	const wantB = `# golang.org/fake/b
-([/._a-zA-Z0-9]+[\\/]fake[\\/])?b/b.go:6:13: call of MyFunc123\(...\)
-([/._a-zA-Z0-9]+[\\/]fake[\\/])?b/b.go:7:11: call of MyFunc123\(...\)
+([/._\-a-zA-Z0-9]+[\\/]fake[\\/])?b/b.go:6:13: call of MyFunc123\(...\)
+([/._\-a-zA-Z0-9]+[\\/]fake[\\/])?b/b.go:7:11: call of MyFunc123\(...\)
 `
 	const wantAJSON = `# golang.org/fake/a
 \{
 	"golang.org/fake/a": \{
 		"findcall": \[
 			\{
-				"posn": "([/._a-zA-Z0-9]+[\\/]fake[\\/])?a/a.go:4:11",
+				"posn": "([/._\-a-zA-Z0-9]+[\\/]fake[\\/])?a/a.go:4:11",
 				"message": "call of MyFunc123\(...\)"
 			\}
 		\]