Few cleanups to type simplification, plus enable it in various jobs (#3018)

go/types/simplify.go

@@ -35,8 +35,6 @@ import (
 // Anytime any of the above cases generates a union as output, the same process
 // is applied to that union recursively.
 func makeSimplifiedUnion(in ...*Type) *Type {
-	d.Chk.True(len(in) > 0)
-
 	ts := make(typeset, len(in))
 	for _, t := range in {
 		// De-cycle so that we handle cycles explicitly below. Otherwise, we would implicitly crawl
@@ -135,6 +133,8 @@ func makeSimplifiedUnionImpl(in typeset) *Type {
 		return out[0]
 	}
 
+	staticTypeCache.Lock()
+	defer staticTypeCache.Unlock()
 	return staticTypeCache.makeUnionType(out...)
 }
 

go/types/simplify_test.go

@@ -148,6 +148,9 @@ func TestMakeSimplifiedUnion(t *testing.T) {
 		in  []*Type
 		out *Type
 	}{
+		// {} -> <empty-union>
+		{[]*Type{},
+			MakeUnionType()},
 		// {bool} -> bool
 		{[]*Type{BoolType},
 			BoolType},

go/types/type_cache.go

@@ -539,11 +539,12 @@ func MakeStructType(name string, fieldNames []string, fieldTypes []*Type) *Type
 }
 
 func MakeUnionType(elemTypes ...*Type) *Type {
-	staticTypeCache.Lock()
-	defer staticTypeCache.Unlock()
 	if enableTypeSimplification {
 		return makeSimplifiedUnion(elemTypes...)
 	}
+
+	staticTypeCache.Lock()
+	defer staticTypeCache.Unlock()
 	return staticTypeCache.makeUnionType(elemTypes...)
 }
 

samples/go/downloader/downloader.go

@@ -55,6 +55,7 @@ func download() (win bool) {
 	var cacheDsArg = flag.String("cache-ds", "", "name of photo-cache dataset")
 	var concurrencyArg = flag.Uint("concurrency", 4, "number of concurrent HTTP calls to retrieve remote resources")
 	verbose.RegisterVerboseFlags(flag.CommandLine)
+	types.RegisterTypeSimplificationFlags(flag.CommandLine)
 	flag.Usage = usage
 	flag.Parse(false)
 

samples/go/face-merge/main.go

@@ -37,6 +37,7 @@ func mergeFaces() {
 	var dbStr = flag.String("db", "", "input database spec")
 	var outDSStr = flag.String("out-ds", "", "output dataset to write to")
 	verbose.RegisterVerboseFlags(flag.CommandLine)
+	types.RegisterTypeSimplificationFlags(flag.CommandLine)
 
 	flag.Usage = usage
 	flag.Parse(false)

samples/go/photo-date-dedup/main.go

@@ -57,6 +57,7 @@ func index() (win bool) {
 	var outDSStr = flag.String("out-ds", "", "output dataset to write to - if empty, defaults to input dataset")
 	var thresh = flag.Int("threshold", 5000, "Number of milliseconds within which to consider photos duplicates")
 	verbose.RegisterVerboseFlags(flag.CommandLine)
+	types.RegisterTypeSimplificationFlags(flag.CommandLine)
 
 	flag.Usage = usage
 	flag.Parse(true)

samples/go/photo-dedup/cmd/photo-dedup/main.go

@@ -12,6 +12,7 @@ import (
 	"github.com/attic-labs/noms/go/config"
 	"github.com/attic-labs/noms/go/datas"
 	"github.com/attic-labs/noms/go/spec"
+	"github.com/attic-labs/noms/go/types"
 	"github.com/attic-labs/noms/go/util/exit"
 	"github.com/attic-labs/noms/go/util/verbose"
 	"github.com/attic-labs/noms/samples/go/photo-dedup/job"
@@ -34,6 +35,7 @@ func main() {
 	var outDSStr = flag.String("out-ds", "", "output dataset to write to")
 	var threshold = flag.Int("threshold", 10, "photo's whose dhash distance is < threshold are grouped together")
 	verbose.RegisterVerboseFlags(flag.CommandLine)
+	types.RegisterTypeSimplificationFlags(flag.CommandLine)
 
 	flag.Usage = usage
 	flag.Parse(false)

samples/go/photo-dedup/cmd/photo-dhash/main.go

@@ -12,6 +12,7 @@ import (
 	"github.com/attic-labs/noms/go/config"
 	"github.com/attic-labs/noms/go/datas"
 	"github.com/attic-labs/noms/go/spec"
+	"github.com/attic-labs/noms/go/types"
 	"github.com/attic-labs/noms/go/util/exit"
 	"github.com/attic-labs/noms/go/util/verbose"
 	"github.com/attic-labs/noms/samples/go/photo-dedup/job"
@@ -34,6 +35,7 @@ func main() {
 	var dbStr = flag.String("db", "", "input database spec")
 	var outDSStr = flag.String("out-ds", "", "output dataset to write to")
 	verbose.RegisterVerboseFlags(flag.CommandLine)
+	types.RegisterTypeSimplificationFlags(flag.CommandLine)
 
 	flag.Usage = usage
 	flag.Parse(false)

samples/go/photo-index/main.go

@@ -64,6 +64,7 @@ func index() (win bool) {
 	var outDSStr = flag.String("out-ds", "", "output dataset to write to - if empty, defaults to input dataset")
 	var indexCovers = flag.Bool("index-covers", false, "the resulting index will contain only the cover Photo, not the entire PhotoGroup")
 	verbose.RegisterVerboseFlags(flag.CommandLine)
+	types.RegisterTypeSimplificationFlags(flag.CommandLine)
 
 	flag.Usage = usage
 	flag.Parse(false)