codegen: assembler for struct with map representation now validates a…

…ll non-optional fields are present.

This continues what #111 did
and adds the same logic to the map representation.  The actual state
tracking works the same way (and was mostly already there).

Rearranged the tests slightly.

Made error messages include both field name and serial key when they
differ due to a rename directive.  (It's possible this error would get
nicer if it used a list of StructField instead of just strings, but it
would also get more complicated.  Maybe revisit later.)

schema/gen/go/genStructReprMap.go

@@ -543,7 +543,21 @@ func (g structReprMapReprBuilderGenerator) emitMapAssemblerMethods(w io.Writer)
 			case maState_finished:
 				panic("invalid state: Finish cannot be called on an assembler that's already finished")
 			}
-			//FIXME check if all required fields are set
+			if ma.s & fieldBits__{{ $type | TypeSymbol }}_sufficient != fieldBits__{{ $type | TypeSymbol }}_sufficient {
+				err := ipld.ErrMissingRequiredField{Missing: make([]string, 0)}
+				{{- range $i, $field := .Type.Fields }}
+				{{- if not $field.IsMaybe}}
+				if ma.s & fieldBit__{{ $type | TypeSymbol }}_{{ $field | FieldSymbolUpper }} == 0 {
+					{{- if $field | $type.RepresentationStrategy.FieldHasRename }}
+					err.Missing = append(err.Missing, "{{ $field.Name }} (serial:\"{{ $field | $type.RepresentationStrategy.GetFieldKey }}\")")
+					{{- else}}
+					err.Missing = append(err.Missing, "{{ $field.Name }}")
+					{{- end}}
+				}
+				{{- end}}
+				{{- end}}
+				return err
+			}
 			ma.state = maState_finished
 			*ma.m = schema.Maybe_Value
 			return nil

schema/gen/go/testStructNesting_test.go → schema/gen/go/testStruct_test.go

@@ -11,6 +11,68 @@ import (
 	"github.com/ipld/go-ipld-prime/schema"
 )
 
+func TestRequiredFields(t *testing.T) {
+	t.Parallel()
+
+	ts := schema.TypeSystem{}
+	ts.Init()
+	adjCfg := &AdjunctCfg{}
+	ts.Accumulate(schema.SpawnString("String"))
+	ts.Accumulate(schema.SpawnStruct("StructOne",
+		[]schema.StructField{
+			schema.SpawnStructField("a", "String", false, false),
+			schema.SpawnStructField("b", "String", false, false),
+		},
+		schema.SpawnStructRepresentationMap(map[string]string{
+			// no renames.  we expect a simpler error message in this case.
+		}),
+	))
+	ts.Accumulate(schema.SpawnStruct("StructTwo",
+		[]schema.StructField{
+			schema.SpawnStructField("a", "String", false, false),
+			schema.SpawnStructField("b", "String", false, false),
+		},
+		schema.SpawnStructRepresentationMap(map[string]string{
+			"b": "z",
+		}),
+	))
+
+	prefix := "struct-required-fields"
+	pkgName := "main"
+	genAndCompileAndTest(t, prefix, pkgName, ts, adjCfg, func(t *testing.T, getPrototypeByName func(string) ipld.NodePrototype) {
+		t.Run("building-type-without-required-fields-errors", func(t *testing.T) {
+			np := getPrototypeByName("StructOne")
+
+			nb := np.NewBuilder()
+			ma, _ := nb.BeginMap(0)
+			err := ma.Finish()
+
+			Wish(t, err, ShouldBeSameTypeAs, ipld.ErrMissingRequiredField{})
+			Wish(t, err.Error(), ShouldEqual, `missing required fields: a,b`)
+		})
+		t.Run("building-representation-without-required-fields-errors", func(t *testing.T) {
+			nrp := getPrototypeByName("StructOne.Repr")
+
+			nb := nrp.NewBuilder()
+			ma, _ := nb.BeginMap(0)
+			err := ma.Finish()
+
+			Wish(t, err, ShouldBeSameTypeAs, ipld.ErrMissingRequiredField{})
+			Wish(t, err.Error(), ShouldEqual, `missing required fields: a,b`)
+		})
+		t.Run("building-representation-with-renames-without-required-fields-errors", func(t *testing.T) {
+			nrp := getPrototypeByName("StructTwo.Repr")
+
+			nb := nrp.NewBuilder()
+			ma, _ := nb.BeginMap(0)
+			err := ma.Finish()
+
+			Wish(t, err, ShouldBeSameTypeAs, ipld.ErrMissingRequiredField{})
+			Wish(t, err.Error(), ShouldEqual, `missing required fields: a,b (serial:"z")`)
+		})
+	})
+}
+
 func TestStructNesting(t *testing.T) {
 	t.Parallel()
 

schema/gen/go/testStructsContainingMaybe_test.go

@@ -171,27 +171,4 @@ func TestStructsContainingMaybe(t *testing.T) {
 			}
 		})
 	})
-
-	genAndCompileAndTest(t, "stroct3", "main", ts, adjCfg, func(t *testing.T, getPrototypeByName func(string) ipld.NodePrototype) {
-		t.Run("insufficient", func(t *testing.T) {
-			nrp := getPrototypeByName("Stroct")
-			t.Run("typed-create", func(t *testing.T) {
-				b := nrp.NewBuilder()
-				mb, err := b.BeginMap(0)
-				if err != nil {
-					t.Fatal(err)
-				}
-				v, err := mb.AssembleEntry("f1")
-				if err != nil {
-					t.Fatal(err)
-				}
-				v.AssignString("v1")
-
-				err = mb.Finish()
-				if _, ok := err.(ipld.ErrMissingRequiredField); !ok {
-					t.Fatalf("Expected error for missing field, got %v", err)
-				}
-			})
-		})
-	})
 }

schema/typeMethods.go

@@ -226,6 +226,11 @@ func (r StructRepresentation_Map) GetFieldKey(field StructField) string {
 	return field.name
 }
 
+func (r StructRepresentation_Map) FieldHasRename(field StructField) bool {
+	_, ok := r.renames[field.name]
+	return ok
+}
+
 func (r StructRepresentation_Stringjoin) GetDelim() string {
 	return r.sep
 }