hcldec must use WithoutOptionalAttributesDeep

When hcldec needs to return a synthetic value, it must use
WithoutOptionalAttributesDeep to ensure the correct type for Null or
Unknown values. Optional attributes are normally removed from the value
type when decoding, but since hcldec is dealing with the decoder spec
directly, the optional attr types are still going to be present in these
cases.

Author: jbardin

hcldec/public_test.go

@@ -137,6 +137,20 @@ func TestDecode(t *testing.T) {
 			cty.NullVal(cty.Number),
 			1, // attribute "a" is required
 		},
+		{
+			``,
+			&AttrSpec{
+				Name: "a",
+				Type: cty.ObjectWithOptionalAttrs(map[string]cty.Type{
+					"attr": cty.String,
+				}, []string{"attr"}),
+			},
+			nil,
+			cty.NullVal(cty.Object(map[string]cty.Type{
+				"attr": cty.String,
+			})),
+			0,
+		},
 
 		{
 			`
@@ -328,6 +342,20 @@ b {
 			cty.NullVal(cty.Map(cty.String)),
 			1, // missing b block
 		},
+		{
+			``,
+			&BlockAttrsSpec{
+				TypeName: "b",
+				ElementType: cty.ObjectWithOptionalAttrs(map[string]cty.Type{
+					"attr": cty.String,
+				}, []string{"attr"}),
+			},
+			nil,
+			cty.NullVal(cty.Map(cty.Object(map[string]cty.Type{
+				"attr": cty.String,
+			}))),
+			0,
+		},
 		{
 			`
 b {

hcldec/spec.go

@@ -200,13 +200,13 @@ func (s *AttrSpec) decode(content *hcl.BodyContent, blockLabels []blockLabel, ct
 	if !exists {
 		// We don't need to check required and emit a diagnostic here, because
 		// that would already have happened when building "content".
-		return cty.NullVal(s.Type), nil
+		return cty.NullVal(s.Type.WithoutOptionalAttributesDeep()), nil
 	}
 
 	if decodeFn := customdecode.CustomExpressionDecoderForType(s.Type); decodeFn != nil {
 		v, diags := decodeFn(attr.Expr, ctx)
 		if v == cty.NilVal {
-			v = cty.UnknownVal(s.Type)
+			v = cty.UnknownVal(s.Type.WithoutOptionalAttributesDeep())
 		}
 		return v, diags
 	}
@@ -229,7 +229,7 @@ func (s *AttrSpec) decode(content *hcl.BodyContent, blockLabels []blockLabel, ct
 		})
 		// We'll return an unknown value of the _correct_ type so that the
 		// incomplete result can still be used for some analysis use-cases.
-		val = cty.UnknownVal(s.Type)
+		val = cty.UnknownVal(s.Type.WithoutOptionalAttributesDeep())
 	} else {
 		val = convVal
 	}
@@ -381,7 +381,7 @@ func (s *BlockSpec) decode(content *hcl.BodyContent, blockLabels []blockLabel, c
 				Subject: &content.MissingItemRange,
 			})
 		}
-		return cty.NullVal(s.Nested.impliedType()), diags
+		return cty.NullVal(s.Nested.impliedType().WithoutOptionalAttributesDeep()), diags
 	}
 
 	if s.Nested == nil {
@@ -478,7 +478,7 @@ func (s *BlockListSpec) decode(content *hcl.BodyContent, blockLabels []blockLabe
 			if u.Unknown() {
 				// If any block Body is unknown, then the entire block value
 				// must be unknown
-				return cty.UnknownVal(s.impliedType()), diags
+				return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 			}
 		}
 
@@ -640,7 +640,7 @@ func (s *BlockTupleSpec) decode(content *hcl.BodyContent, blockLabels []blockLab
 			if u.Unknown() {
 				// If any block Body is unknown, then the entire block value
 				// must be unknown
-				return cty.UnknownVal(s.impliedType()), diags
+				return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 			}
 		}
 
@@ -763,7 +763,7 @@ func (s *BlockSetSpec) decode(content *hcl.BodyContent, blockLabels []blockLabel
 			if u.Unknown() {
 				// If any block Body is unknown, then the entire block value
 				// must be unknown
-				return cty.UnknownVal(s.impliedType()), diags
+				return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 			}
 		}
 
@@ -922,7 +922,7 @@ func (s *BlockMapSpec) decode(content *hcl.BodyContent, blockLabels []blockLabel
 			if u.Unknown() {
 				// If any block Body is unknown, then the entire block value
 				// must be unknown
-				return cty.UnknownVal(s.impliedType()), diags
+				return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 			}
 		}
 
@@ -1076,7 +1076,7 @@ func (s *BlockObjectSpec) decode(content *hcl.BodyContent, blockLabels []blockLa
 			if u.Unknown() {
 				// If any block Body is unknown, then the entire block value
 				// must be unknown
-				return cty.UnknownVal(s.impliedType()), diags
+				return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 			}
 		}
 
@@ -1250,7 +1250,7 @@ func (s *BlockAttrsSpec) decode(content *hcl.BodyContent, blockLabels []blockLab
 				Subject: &content.MissingItemRange,
 			})
 		}
-		return cty.NullVal(cty.Map(s.ElementType)), diags
+		return cty.NullVal(cty.Map(s.ElementType).WithoutOptionalAttributesDeep()), diags
 	}
 	if other != nil {
 		diags = append(diags, &hcl.Diagnostic{
@@ -1513,7 +1513,7 @@ func (s *TransformExprSpec) decode(content *hcl.BodyContent, blockLabels []block
 		// We won't try to run our function in this case, because it'll probably
 		// generate confusing additional errors that will distract from the
 		// root cause.
-		return cty.UnknownVal(s.impliedType()), diags
+		return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 	}
 
 	chiCtx := s.TransformCtx.NewChild()
@@ -1569,7 +1569,7 @@ func (s *TransformFuncSpec) decode(content *hcl.BodyContent, blockLabels []block
 		// We won't try to run our function in this case, because it'll probably
 		// generate confusing additional errors that will distract from the
 		// root cause.
-		return cty.UnknownVal(s.impliedType()), diags
+		return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 	}
 
 	resultVal, err := s.Func.Call([]cty.Value{wrappedVal})
@@ -1583,7 +1583,7 @@ func (s *TransformFuncSpec) decode(content *hcl.BodyContent, blockLabels []block
 			Detail:   fmt.Sprintf("Decoder transform returned an error: %s", err),
 			Subject:  s.sourceRange(content, blockLabels).Ptr(),
 		})
-		return cty.UnknownVal(s.impliedType()), diags
+		return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 	}
 
 	return resultVal, diags
@@ -1637,7 +1637,7 @@ func (s *RefineValueSpec) decode(content *hcl.BodyContent, blockLabels []blockLa
 		// We won't try to run our function in this case, because it'll probably
 		// generate confusing additional errors that will distract from the
 		// root cause.
-		return cty.UnknownVal(s.impliedType()), diags
+		return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 	}
 
 	return wrappedVal.RefineWith(s.Refine), diags
@@ -1658,7 +1658,6 @@ func (s *RefineValueSpec) sourceRange(content *hcl.BodyContent, blockLabels []bl
 // The Subject field of the returned Diagnostic is optional. If not
 // specified, it is automatically populated with the range covered by
 // the wrapped spec.
-//
 type ValidateSpec struct {
 	Wrapped Spec
 	Func    func(value cty.Value) hcl.Diagnostics
@@ -1674,7 +1673,7 @@ func (s *ValidateSpec) decode(content *hcl.BodyContent, blockLabels []blockLabel
 		// We won't try to run our function in this case, because it'll probably
 		// generate confusing additional errors that will distract from the
 		// root cause.
-		return cty.UnknownVal(s.impliedType()), diags
+		return cty.UnknownVal(s.impliedType().WithoutOptionalAttributesDeep()), diags
 	}
 
 	validateDiags := s.Func(wrappedVal)