Add unit test

Author: owen-mc

go/extractor/cli/go-autobuilder/go-autobuilder_test.go

@@ -33,3 +33,56 @@ func TestParseGoVersion(t *testing.T) {
 		}
 	}
 }
+
+func TestGetVersionToInstall(t *testing.T) {
+	tests := map[versionInfo]string{
+		// checkForUnsupportedVersions()
+
+		// go.mod version below minGoVersion
+		{"0.0", true, "1.20.3", true}: "",
+		{"0.0", true, "9999.0", true}: "",
+		{"0.0", true, "1.2.2", true}:  "",
+		{"0.0", true, "", false}:      "",
+		// go.mod version above maxGoVersion
+		{"9999.0", true, "1.20.3", true}:   "",
+		{"9999.0", true, "9999.0.1", true}: "",
+		{"9999.0", true, "1.1", true}:      "",
+		{"9999.0", true, "", false}:        "",
+		// Go installation found with version below minGoVersion
+		{"1.20", true, "1.2.2", true}: "",
+		{"1.11", true, "1.2.2", true}: "",
+		{"", false, "1.2.2", true}:    "",
+		// Go installation found with version above maxGoVersion
+		{"1.20", true, "9999.0.1", true}: "",
+		{"1.11", true, "9999.0.1", true}: "",
+		{"", false, "9999.0.1", true}:    "",
+
+		// checkForVersionsNotFound()
+
+		// Go installation not found, go.mod version in supported range
+		{"1.20", true, "", false}: "1.20",
+		{"1.11", true, "", false}: "1.11",
+		// Go installation not found, go.mod not found
+		{"", false, "", false}: maxGoVersion,
+		// Go installation found with version in supported range, go.mod not found
+		{"", false, "1.11.13", true}: "",
+		{"", false, "1.20.3", true}:  "",
+
+		// compareVersions()
+
+		// Go installation found with version in supported range, go.mod version in supported range and go.mod version > go installation version
+		{"1.20", true, "1.11.13", true}: "1.20",
+		{"1.20", true, "1.12", true}:    "1.20",
+		// Go installation found with version in supported range, go.mod version in supported range and go.mod version <= go installation version
+		// (Note comparisons ignore the patch version)
+		{"1.11", true, "1.20", true}:   "",
+		{"1.11", true, "1.20.3", true}: "",
+		{"1.20", true, "1.20.3", true}: "",
+	}
+	for input, expected := range tests {
+		_, actual := getVersionToInstall(input)
+		if actual != expected {
+			t.Errorf("Expected getVersionToInstall(\"%s\") to be \"%s\", but got \"%s\".", input, expected, actual)
+		}
+	}
+}