[mdatagen] Fix bug where Histograms were marked as not supporting temporaly aggregation (#12168)

See
https://github.com/open-telemetry/opentelemetry-proto/blob/main/opentelemetry/proto/metrics/v1/metrics.proto#L254

Signed-off-by: Bogdan Drutu <[email protected]>

Author: bogdandrutu

.chloggen/fix-bug-histogram-aggregation.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: mdatagen
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Fix bug where Histograms were marked as not supporting temporaly aggregation
+
+# One or more tracking issues or pull requests related to the change
+issues: [12168]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [api, user]

cmd/mdatagen/internal/metric.go

@@ -350,7 +350,7 @@ func (d *Histogram) HasMonotonic() bool {
 }
 
 func (d *Histogram) HasAggregated() bool {
-	return false
+	return true
 }
 
 func (d *Histogram) Instrument() string {

cmd/mdatagen/internal/metric_test.go

@@ -29,7 +29,7 @@ func TestMetricData(t *testing.T) {
 		{&Sum{Async: true}, "Sum", true, true, "ObservableUpDownCounter", true},
 		{&Sum{MetricValueType: MetricValueType{pmetric.NumberDataPointValueTypeInt}, Async: true}, "Sum", true, true, "Int64ObservableUpDownCounter", true},
 		{&Sum{MetricValueType: MetricValueType{pmetric.NumberDataPointValueTypeDouble}, Async: true}, "Sum", true, true, "Float64ObservableUpDownCounter", true},
-		{&Histogram{}, "Histogram", false, false, "Histogram", false},
+		{&Histogram{}, "Histogram", true, false, "Histogram", false},
 	} {
 		assert.Equal(t, arg.wantType, arg.metricData.Type())
 		assert.Equal(t, arg.wantHasAggregated, arg.metricData.HasAggregated())