1 files changed, 79 insertions, 0 deletions
diff --git a/internal/fuzzy/symbol_test.go b/internal/fuzzy/symbol_test.go
new file mode 100644
index 000000000..df74bbe0d
--- /dev/null
+++ b/internal/fuzzy/symbol_test.go
@@ -0,0 +1,79 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fuzzy_test
+
+import (
+	"testing"
+
+	. "golang.org/x/tools/internal/fuzzy"
+)
+
+func TestSymbolMatchIndex(t *testing.T) {
+	tests := []struct {
+		pattern, input string
+		want           int
+	}{
+		{"test", "foo.TestFoo", 4},
+		{"test", "test", 0},
+		{"test", "Test", 0},
+		{"test", "est", -1},
+		{"t", "shortest", 7},
+		{"", "foo", -1},
+		{"", string([]rune{0}), -1}, // verify that we don't default to an empty pattern.
+		{"anything", "", -1},
+	}
+
+	for _, test := range tests {
+		matcher := NewSymbolMatcher(test.pattern)
+		if got, _ := matcher.Match([]string{test.input}); got != test.want {
+			t.Errorf("NewSymbolMatcher(%q).Match(%q) = %v, _, want %v, _", test.pattern, test.input, got, test.want)
+		}
+	}
+}
+
+func TestSymbolRanking(t *testing.T) {
+	matcher := NewSymbolMatcher("test")
+
+	// symbols to match, in ascending order of ranking.
+	symbols := []string{
+		"this.is.better.than.most",
+		"test.foo.bar",
+		"atest",
+		"thebest",
+		"test.foo",
+		"test.foo",
+		"tTest",
+		"testage",
+		"foo.test",
+		"test",
+	}
+	prev := 0.0
+	for _, sym := range symbols {
+		_, score := matcher.Match([]string{sym})
+		t.Logf("Match(%q) = %v", sym, score)
+		if score < prev {
+			t.Errorf("Match(%q) = _, %v, want > %v", sym, score, prev)
+		}
+		prev = score
+	}
+}
+
+func TestChunkedMatch(t *testing.T) {
+	matcher := NewSymbolMatcher("test")
+
+	chunked := [][]string{
+		{"test"},
+		{"", "test"},
+		{"test", ""},
+		{"te", "st"},
+	}
+
+	for _, chunks := range chunked {
+		offset, score := matcher.Match(chunks)
+		if offset != 0 || score != 1.0 {
+			t.Errorf("Match(%v) = %v, %v, want 0, 1.0", chunks, offset, score)
+		}
+	}
+}