Parser test cleanup (#3977)

* parser test cleanup

- Test against the exported package functions instead of the private functions.

* Improves readability of TestParseSeries

- Moves package function closer to parser function

promql/parse.go

@@ -104,14 +104,6 @@ func ParseMetricSelector(input string) (m []*labels.Matcher, err error) {
 	return vs.LabelMatchers, nil
 }
 
-// parseSeriesDesc parses the description of a time series.
-func parseSeriesDesc(input string) (labels.Labels, []sequenceValue, error) {
-	p := newParser(input)
-	p.lex.seriesDesc = true
-
-	return p.parseSeriesDesc()
-}
-
 // newParser returns a new parser.
 func newParser(input string) *parser {
 	p := &parser{
@@ -167,6 +159,14 @@ func (v sequenceValue) String() string {
 	return fmt.Sprintf("%f", v.value)
 }
 
+// parseSeriesDesc parses the description of a time series.
+func parseSeriesDesc(input string) (labels.Labels, []sequenceValue, error) {
+	p := newParser(input)
+	p.lex.seriesDesc = true
+
+	return p.parseSeriesDesc()
+}
+
 // parseSeriesDesc parses a description of a time series into its metric and value sequence.
 func (p *parser) parseSeriesDesc() (m labels.Labels, vals []sequenceValue, err error) {
 	defer p.recover(&err)

promql/parse_test.go

@@ -139,7 +139,8 @@ var testExpr = []struct {
 			},
 		},
 	}, {
-		input: "-some_metric", expected: &UnaryExpr{
+		input: "-some_metric",
+		expected: &UnaryExpr{
 			Op: itemSUB,
 			Expr: &VectorSelector{
 				Name: "some_metric",
@@ -149,7 +150,8 @@ var testExpr = []struct {
 			},
 		},
 	}, {
-		input: "+some_metric", expected: &UnaryExpr{
+		input: "+some_metric",
+		expected: &UnaryExpr{
 			Op: itemADD,
 			Expr: &VectorSelector{
 				Name: "some_metric",
@@ -1396,9 +1398,7 @@ var testExpr = []struct {
 
 func TestParseExpressions(t *testing.T) {
 	for _, test := range testExpr {
-		parser := newParser(test.input)
-
-		expr, err := parser.parseExpr()
+		expr, err := ParseExpr(test.input)
 
 		// Unexpected errors are always caused by a bug.
 		if err == errUnexpected {
@@ -1409,6 +1409,7 @@ func TestParseExpressions(t *testing.T) {
 			t.Errorf("error in input '%s'", test.input)
 			t.Fatalf("could not parse: %s", err)
 		}
+
 		if test.fail && err != nil {
 			if !strings.Contains(err.Error(), test.errMsg) {
 				t.Errorf("unexpected error on input '%s'", test.input)
@@ -1417,24 +1418,6 @@ func TestParseExpressions(t *testing.T) {
 			continue
 		}
 
-		err = parser.typecheck(expr)
-		if !test.fail && err != nil {
-			t.Errorf("error on input '%s'", test.input)
-			t.Fatalf("typecheck failed: %s", err)
-		}
-
-		if test.fail {
-			if err != nil {
-				if !strings.Contains(err.Error(), test.errMsg) {
-					t.Errorf("unexpected error on input '%s'", test.input)
-					t.Fatalf("expected error to contain %q but got %q", test.errMsg, err)
-				}
-				continue
-			}
-			t.Errorf("error on input '%s'", test.input)
-			t.Fatalf("failure expected, but passed with result: %q", expr)
-		}
-
 		if !reflect.DeepEqual(expr, test.expected) {
 			t.Errorf("error on input '%s'", test.input)
 			t.Fatalf("no match\n\nexpected:\n%s\ngot: \n%s\n", Tree(test.expected), Tree(expr))
@@ -1444,9 +1427,7 @@ func TestParseExpressions(t *testing.T) {
 
 // NaN has no equality. Thus, we need a separate test for it.
 func TestNaNExpression(t *testing.T) {
-	parser := newParser("NaN")
-
-	expr, err := parser.parseExpr()
+	expr, err := ParseExpr("NaN")
 	if err != nil {
 		t.Errorf("error on input 'NaN'")
 		t.Fatalf("coud not parse: %s", err)
@@ -1677,9 +1658,7 @@ var testStatement = []struct {
 
 func TestParseStatements(t *testing.T) {
 	for _, test := range testStatement {
-		parser := newParser(test.input)
-
-		stmts, err := parser.parseStmts()
+		stmts, err := ParseStmts(test.input)
 
 		// Unexpected errors are always caused by a bug.
 		if err == errUnexpected {
@@ -1694,20 +1673,6 @@ func TestParseStatements(t *testing.T) {
 			continue
 		}
 
-		err = parser.typecheck(stmts)
-		if !test.fail && err != nil {
-			t.Errorf("error in input: \n\n%s\n", test.input)
-			t.Fatalf("typecheck failed: %s", err)
-		}
-
-		if test.fail {
-			if err != nil {
-				continue
-			}
-			t.Errorf("error in input: \n\n%s\n", test.input)
-			t.Fatalf("failure expected, but passed")
-		}
-
 		if !reflect.DeepEqual(stmts, test.expected) {
 			t.Errorf("error in input: \n\n%s\n", test.input)
 			t.Fatalf("no match\n\nexpected:\n%s\ngot: \n%s\n", Tree(test.expected), Tree(stmts))
@@ -1791,30 +1756,24 @@ func newSeq(vals ...float64) (res []sequenceValue) {
 
 func TestParseSeries(t *testing.T) {
 	for _, test := range testSeries {
-		parser := newParser(test.input)
-		parser.lex.seriesDesc = true
-
-		metric, vals, err := parser.parseSeriesDesc()
+		metric, vals, err := parseSeriesDesc(test.input)
 
 		// Unexpected errors are always caused by a bug.
 		if err == errUnexpected {
 			t.Fatalf("unexpected error occurred")
 		}
 
-		if !test.fail && err != nil {
-			t.Errorf("error in input: \n\n%s\n", test.input)
-			t.Fatalf("could not parse: %s", err)
-		}
-		if test.fail && err != nil {
-			continue
-		}
-
 		if test.fail {
 			if err != nil {
 				continue
 			}
 			t.Errorf("error in input: \n\n%s\n", test.input)
 			t.Fatalf("failure expected, but passed")
+		} else {
+			if err != nil {
+				t.Errorf("error in input: \n\n%s\n", test.input)
+				t.Fatalf("could not parse: %s", err)
+			}
 		}
 
 		require.Equal(t, test.expectedMetric, metric)