[bugfix] logql: vectorExpr run fail when query_range: parallelise_shardable_queries: true (#7045)

…hardable_queries: true

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**What this PR does / why we need it**:
A grafana error occurred when I deployed the vector(0) function to our
online loki cluster.
It was finally found because online loki has a configuration


`unexpected expr type (*syntax.VectorExpr) for ASTMapper type
(logql.ShardMapper)
`
```yaml
query_range:
   parallelise_shardable_queries: true
```
**Which issue(s) this PR fixes**:
Fixes #

**Special notes for your reviewer**:
error snapssnapshot

![image](https://user-images.githubusercontent.com/9583245/188357957-e573e589-a789-4e5e-a1c3-b91c019ceb62.png)
with this pr，success snapshot

![image](https://user-images.githubusercontent.com/9583245/188358036-5ca0d9be-c2b6-4516-807c-c027445ee62d.png)

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**Checklist**
- [ ] Documentation added
- [ ] Tests updated
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pkg/logql/shardmapper.go

@@ -74,6 +74,8 @@ func (m ShardMapper) Map(expr syntax.Expr, r *downstreamRecorder) (syntax.Expr,
 	switch e := expr.(type) {
 	case *syntax.LiteralExpr:
 		return e, nil
+	case *syntax.VectorExpr:
+		return e, nil
 	case *syntax.MatchersExpr, *syntax.PipelineExpr:
 		return m.mapLogSelectorExpr(e.(syntax.LogSelectorExpr), r)
 	case *syntax.VectorAggregationExpr:

pkg/logql/shardmapper_test.go

@@ -782,6 +782,64 @@ func TestMapping(t *testing.T) {
 				},
 			},
 		},
+		{
+			in: `vector(0) or sum (rate({foo="bar"}[5m]))`,
+			expr: &syntax.BinOpExpr{
+				Op: syntax.OpTypeOr,
+				Opts: &syntax.BinOpOptions{
+					ReturnBool:     false,
+					VectorMatching: &syntax.VectorMatching{Card: syntax.CardOneToOne},
+				},
+				SampleExpr: &syntax.VectorExpr{Val: 0},
+				RHS: &syntax.VectorAggregationExpr{
+					Operation: syntax.OpTypeSum,
+					Grouping:  &syntax.Grouping{},
+					Left: &ConcatSampleExpr{
+						DownstreamSampleExpr: DownstreamSampleExpr{
+							shard: &astmapper.ShardAnnotation{
+								Shard: 0,
+								Of:    2,
+							},
+							SampleExpr: &syntax.VectorAggregationExpr{
+								Grouping:  &syntax.Grouping{},
+								Operation: syntax.OpTypeSum,
+								Left: &syntax.RangeAggregationExpr{
+									Operation: syntax.OpRangeTypeRate,
+									Left: &syntax.LogRange{
+										Left: &syntax.MatchersExpr{
+											Mts: []*labels.Matcher{mustNewMatcher(labels.MatchEqual, "foo", "bar")},
+										},
+										Interval: 5 * time.Minute,
+									},
+								},
+							},
+						},
+						next: &ConcatSampleExpr{
+							DownstreamSampleExpr: DownstreamSampleExpr{
+								shard: &astmapper.ShardAnnotation{
+									Shard: 1,
+									Of:    2,
+								},
+								SampleExpr: &syntax.VectorAggregationExpr{
+									Grouping:  &syntax.Grouping{},
+									Operation: syntax.OpTypeSum,
+									Left: &syntax.RangeAggregationExpr{
+										Operation: syntax.OpRangeTypeRate,
+										Left: &syntax.LogRange{
+											Left: &syntax.MatchersExpr{
+												Mts: []*labels.Matcher{mustNewMatcher(labels.MatchEqual, "foo", "bar")},
+											},
+											Interval: 5 * time.Minute,
+										},
+									},
+								},
+							},
+							next: nil,
+						},
+					},
+				},
+			},
+		},
 		// sum(max) should not shard the maxes
 		{
 			in: `sum(max(rate({foo="bar"}[5m])))`,