fix(gen/tables): passing seed to tables generator (#4866)

* fix(gen/tables): passing seed to tables generator Adding seed to tables generator to get the very same sequence each time(helpful in writing test) at the moment the seed defaults to the current time, which generates a different sequence each time. useful in #4307 * fix: passing pointer for Seed so that it defaults to nil not zero
influxdata · Jun 13, 2022 · 2ceafc4 · 2ceafc4
1 parent 9e77d56
commit 2ceafc4
Show file tree

Hide file tree

Showing 4 changed files with 40 additions and 1 deletion.
diff --git a/libflux/go/libflux/buildinfo.gen.go b/libflux/go/libflux/buildinfo.gen.go
@@ -257,7 +257,8 @@ var sourceHashes = map[string]string{
 	"stdlib/internal/boolean/boolean.flux":                                                        "1c0a1564911dd5f4c35c17efb32158ab31c51b20ac0f25175545e50aadc87c94",
 	"stdlib/internal/debug/debug.flux":                                                            "104485f6a8d6e1cd2fc8111367687fed4cef2a63b5a7657124571b89b0e2420c",
 	"stdlib/internal/debug/debug_test.flux":                                                       "063349cd314ed79906a96d84ed3c6829c734d1607e0bbae0654bdc9e22210e3c",
-	"stdlib/internal/gen/gen.flux":                                                                "320c005cffe97f28324a21054089cf78a2e6c511c639c4c0d1df727e46072c05",
+	"stdlib/internal/gen/gen.flux":                                                                "680830a7337f5f6f72927e8c43248138e77d719ef09df4af06f2d00f7932d730",
+	"stdlib/internal/gen/tables_test.flux":                                                        "14a3d3542aa0815bf3fb912b045c23161322acff731bfa04ce380c5da9866654",
 	"stdlib/internal/influxql/influxql.flux":                                                      "51739e7d9026cae356fdef79a4340d2bda7fc10d1daa1a7adeae06014f85049c",
 	"stdlib/internal/location/location.flux":                                                      "e810d8264dd1590f9556259cfa76272c8e5698a0262509d0ca12bfd4c71342f5",
 	"stdlib/internal/promql/join_test.flux":                                                       "87fde732a159a2cffb81dbc21eebf70df352b69e04781e6e4526f57336b30146",

diff --git a/stdlib/internal/gen/gen.flux b/stdlib/internal/gen/gen.flux
@@ -8,8 +8,10 @@ package gen
 // - n: Number of rows to generate.
 // - nulls: Percentage chance that a null value will be used in the input. Valid value range is `[0.0 - 1.0]`.
 // - tags: Set of tags with their cardinality to generate.
+// - seed: Pass seed to tables generator to get the very same sequence each time
 builtin tables : (
         n: int,
         ?nulls: float,
         ?tags: [{name: string, cardinality: int}],
+        ?seed: int,
     ) => stream[{A with _time: time, _value: float}]
diff --git a/stdlib/internal/gen/tables.go b/stdlib/internal/gen/tables.go
@@ -26,6 +26,7 @@ type TablesOpSpec struct {
 	N     int     `json:"n"`
 	Tags  []Tag   `json:"tags,omitempty"`
 	Nulls float64 `json:"nulls,omitempty"`
+	Seed  *int64  `json:"Seed,omitempty"`
 }
 
 func init() {
@@ -91,6 +92,12 @@ func createTablesOpSpec(args flux.Arguments, a *flux.Administration) (flux.Opera
 		spec.Nulls = nulls
 	}
 
+	if seed, ok, err := args.GetInt("seed"); err != nil {
+		return nil, err
+	} else if ok {
+		spec.Seed = &seed
+	}
+
 	return spec, nil
 }
 
@@ -116,6 +123,7 @@ func newTablesProcedure(qs flux.OperationSpec, pa plan.Administration) (plan.Pro
 	schema := gen.Schema{
 		NumPoints: spec.N,
 		Nulls:     spec.Nulls,
+		Seed:      spec.Seed,
 	}
 
 	if len(spec.Tags) > 0 {

diff --git a/stdlib/internal/gen/tables_test.flux b/stdlib/internal/gen/tables_test.flux
@@ -0,0 +1,28 @@
+package gen
+
+
+import "array"
+import "testing"
+import "internal/gen"
+import "internal/debug"
+
+option now = () => 2030-01-01T00:00:00Z
+
+testcase gen_tables_seed {
+    got =
+        gen.tables(n: 5, seed: 123)
+            |> drop(columns: ["_time"])
+
+    want =
+        array.from(
+            rows: [
+                {_value: -39.7289264835779},
+                {_value: 3.561659508431711},
+                {_value: 34.956531511845476},
+                {_value: -53.72013420347799},
+                {_value: 49.20701082669753},
+            ],
+        )
+
+    testing.diff(got: got, want: want)
+}