zcldec: BlockSpec decode implementation

zcldec/public_test.go

@@ -55,6 +55,76 @@ func TestDecode(t *testing.T) {
 			cty.NumberIntVal(1),
 			0,
 		},
+		{
+			``,
+			&AttrSpec{
+				Name:     "a",
+				Type:     cty.Number,
+				Required: true,
+			},
+			nil,
+			cty.DynamicVal,
+			1, // attribute "a" is required
+		},
+
+		{
+			`
+b {
+}
+`,
+			&BlockSpec{
+				TypeName: "b",
+				Nested:   ObjectSpec{},
+			},
+			nil,
+			cty.EmptyObjectVal,
+			0,
+		},
+		{
+			``,
+			&BlockSpec{
+				TypeName: "b",
+				Nested:   ObjectSpec{},
+			},
+			nil,
+			cty.NullVal(cty.DynamicPseudoType),
+			0,
+		},
+		{
+			`a {}`,
+			&BlockSpec{
+				TypeName: "b",
+				Nested:   ObjectSpec{},
+			},
+			nil,
+			cty.NullVal(cty.DynamicPseudoType),
+			1, // blocks of type "a" are not supported
+		},
+		{
+			``,
+			&BlockSpec{
+				TypeName: "b",
+				Nested:   ObjectSpec{},
+				Required: true,
+			},
+			nil,
+			cty.NullVal(cty.DynamicPseudoType),
+			1, // a block of type "b" is required
+		},
+		{
+			`
+b {}
+b {}
+`,
+			&BlockSpec{
+				TypeName: "b",
+				Nested:   ObjectSpec{},
+				Required: true,
+			},
+			nil,
+			cty.EmptyObjectVal,
+			1, // only one "b" block is allowed
+		},
 	}
 
 	for i, test := range tests {

zcldec/spec.go

@@ -184,6 +184,15 @@ func (s *BlockSpec) visitSameBodyChildren(cb visitFunc) {
 	// leaf node ("Nested" does not use the same body)
 }
 
+// blockSpec implementation
+func (s *BlockSpec) blockHeaderSchemata() []zcl.BlockHeaderSchema {
+	return []zcl.BlockHeaderSchema{
+		{
+			Type: s.TypeName,
+		},
+	}
+}
+
 func (s *BlockSpec) decode(content *zcl.BodyContent, block *zcl.Block, ctx *zcl.EvalContext) (cty.Value, zcl.Diagnostics) {
 	var diags zcl.Diagnostics
 
@@ -223,6 +232,9 @@ func (s *BlockSpec) decode(content *zcl.BodyContent, block *zcl.Block, ctx *zcl.
 		return cty.NullVal(cty.DynamicPseudoType), diags
 	}
 
+	if s.Nested == nil {
+		panic("BlockSpec with no Nested Spec")
+	}
 	val, _, childDiags := decode(childBlock.Body, childBlock, ctx, s.Nested, false)
 	diags = append(diags, childDiags...)
 	return val, diags