fix NH load expression with incrementation more than once

Signed-off-by: Neeraj Gartia <neerajgartia211002@gmail.com>

promql/parser/lex.go

@@ -512,7 +512,7 @@ func lexHistogram(l *Lexer) stateFn {
 		l.histogramState = histogramStateNone
 		l.next()
 		l.emit(TIMES)
-		return lexNumber
+		return lexValueSequence
 	case histogramStateAdd:
 		l.histogramState = histogramStateNone
 		l.next()

promql/parser/lex_test.go

@@ -691,6 +691,42 @@ var tests = []struct {
 				},
 				seriesDesc: true,
 			},
+			{
+				input: `{} {{sum:1}}+{{sum:0}}x2 {{sum:1}}+{{sum:0}}x3`,
+				expected: []Item{
+					{LEFT_BRACE, 0, `{`},
+					{RIGHT_BRACE, 1, `}`},
+					{SPACE, 2, ` `},
+					{OPEN_HIST, 3, `{{`},
+					{SUM_DESC, 5, `sum`},
+					{COLON, 8, `:`},
+					{NUMBER, 9, `1`},
+					{CLOSE_HIST, 10, `}}`},
+					{ADD, 12, `+`},
+					{OPEN_HIST, 13, `{{`},
+					{SUM_DESC, 15, `sum`},
+					{COLON, 18, `:`},
+					{NUMBER, 19, `0`},
+					{CLOSE_HIST, 20, `}}`},
+					{TIMES, 22, `x`},
+					{NUMBER, 23, `2`},
+					{SPACE, 24, ` `},
+					{OPEN_HIST, 25, `{{`},
+					{SUM_DESC, 27, `sum`},
+					{COLON, 30, `:`},
+					{NUMBER, 31, `1`},
+					{CLOSE_HIST, 32, `}}`},
+					{ADD, 34, `+`},
+					{OPEN_HIST, 35, `{{`},
+					{SUM_DESC, 37, `sum`},
+					{COLON, 40, `:`},
+					{NUMBER, 41, `0`},
+					{CLOSE_HIST, 42, `}}`},
+					{TIMES, 44, `x`},
+					{NUMBER, 45, `3`},
+				},
+				seriesDesc: true,
+			},
 		},
 	},
 	{

promql/parser/parse_test.go

@@ -4371,6 +4371,30 @@ func TestParseHistogramSeries(t *testing.T) {
 				},
 			},
 		},
+		{
+			name:  "series with two different increments",
+			input: `{} {{sum:1}}+{{sum:1}}x2 {{sum:2}}+{{sum:2}}x2`,
+			expected: []histogram.FloatHistogram{
+				{
+					Sum: 1,
+				},
+				{
+					Sum: 2,
+				},
+				{
+					Sum: 3,
+				},
+				{
+					Sum: 2,
+				},
+				{
+					Sum: 4,
+				},
+				{
+					Sum: 6,
+				},
+			},
+		},
 		{
 			name:  "series with decrement",
 			input: `{} {{buckets:[5 10 7] schema:1}}-{{buckets:[1 2 3] schema:1}}x2`,

promql/promqltest/testdata/native_histograms.test

@@ -57,7 +57,7 @@ clear
 
 # Repeat the same histogram 10 times.
 load 5m
-	multi_histogram	{{schema:0 sum:5 count:4 buckets:[1 2 1]}}x10
+	multi_histogram	{{schema:0 sum:5 count:4 buckets:[1 2 1]}}x10 {{schema:0 sum:5 count:4 buckets:[1 2 1]}}+{{}}x10
 
 eval instant at 5m histogram_count(multi_histogram)
 	{} 4