WIP

internal/configs/named_values.go

@@ -346,6 +346,9 @@ type Output struct {
 	Sensitive   bool
 	Ephemeral   bool
 
+	Deprecated        bool
+	DeprecatedMessage string
+
 	Preconditions []*CheckRule
 
 	DescriptionSet bool
@@ -402,6 +405,22 @@ func decodeOutputBlock(block *hcl.Block, override bool) (*Output, hcl.Diagnostic
 		o.EphemeralSet = true
 	}
 
+	if attr, exists := content.Attributes["deprecated"]; exists {
+		msg, msgDiags := attr.Expr.Value(nil)
+		diags = append(diags, msgDiags...)
+		if msg.Type() != cty.String || !msg.IsWhollyKnown() || msg.IsNull() {
+			diags = append(diags, &hcl.Diagnostic{
+				Severity: hcl.DiagError,
+				Summary:  "Deprecated message must be a known, non-empty string",
+				Detail:   "The deprecated argument must be a known, non-empty string.",
+				Subject:  &attr.Range,
+			})
+		} else {
+			o.DeprecatedMessage = msg.AsString()
+			o.Deprecated = true
+		}
+	}
+
 	if attr, exists := content.Attributes["depends_on"]; exists {
 		deps, depsDiags := DecodeDependsOn(attr)
 		diags = append(diags, depsDiags...)
@@ -525,6 +544,9 @@ var outputBlockSchema = &hcl.BodySchema{
 		{
 			Name: "ephemeral",
 		},
+		{
+			Name: "deprecated",
+		},
 	},
 	Blocks: []hcl.BlockHeaderSchema{
 		{Type: "precondition"},

internal/configs/named_values_test.go

@@ -48,3 +48,30 @@ func TestVariableInvalidDefault(t *testing.T) {
 		}
 	}
 }
+
+func TestOutputDeprecation(t *testing.T) {
+	src := `
+		output "foo" {
+			value = "bar"
+			deprecated = "This output is deprecated"
+		}
+	`
+
+	hclF, diags := hclsyntax.ParseConfig([]byte(src), "test.tf", hcl.InitialPos)
+	if diags.HasErrors() {
+		t.Fatal(diags.Error())
+	}
+
+	b, diags := parseConfigFile(hclF.Body, nil, false, false)
+	if diags.HasErrors() {
+		t.Fatalf("unexpected error: %q", diags)
+	}
+
+	if b.Outputs[0].Deprecated != true {
+		t.Fatalf("expected output to be deprecated")
+	}
+
+	if b.Outputs[0].DeprecatedMessage != "This output is deprecated" {
+		t.Fatalf("expected output to have deprecation message")
+	}
+}

internal/terraform/context_plan2_test.go

@@ -6068,3 +6068,59 @@ data "test_data_source" "foo" {
 	_, diags := ctx.Plan(m, states.NewState(), SimplePlanOpts(plans.NormalMode, testInputValuesUnset(m.Module.Variables)))
 	assertNoErrors(t, diags)
 }
+
+func TestContext2Plan_deprecated_output(t *testing.T) {
+	m := testModuleInline(t, map[string]string{
+		"mod/main.tf": `
+output "old" {
+    deprecated = "Please stop using this"
+    value = "old"
+}
+
+output "old-and-unused" {
+    deprecated = "This should not show up in the errors, we are not using it"
+    value = "old"
+}
+
+output "new" {
+    value = "foo"
+}
+`,
+		"main.tf": `
+module "mod" {
+    source = "./mod"
+}
+
+resource "test_resource" "test" {
+    attr = module.mod.old
+}
+
+resource "test_resource" "test2" {
+    attr = module.mod.new
+}
+`,
+	})
+
+	p := new(testing_provider.MockProvider)
+	p.GetProviderSchemaResponse = getProviderSchemaResponseFromProviderSchema(&providerSchema{
+		ResourceTypes: map[string]*configschema.Block{
+			"test_resource": {
+				Attributes: map[string]*configschema.Attribute{
+					"attr": {
+						Type:     cty.String,
+						Computed: true,
+					},
+				},
+			},
+		},
+	})
+
+	ctx := testContext2(t, &ContextOpts{
+		Providers: map[addrs.Provider]providers.Factory{
+			addrs.NewDefaultProvider("test"): testProviderFuncFixed(p),
+		},
+	})
+
+	_, diags := ctx.Plan(m, states.NewState(), SimplePlanOpts(plans.NormalMode, testInputValuesUnset(m.Module.Variables)))
+	assertDiagnosticsMatch(t, diags, []tfdiags.Diagnostic{})
+}

internal/terraform/node_resource_abstract.go

@@ -545,6 +545,30 @@ func (n *NodeAbstractResource) readResourceInstanceStateDeposed(ctx EvalContext,
 	return obj, diags
 }
 
+func (n *NodeAbstractResource) validateUsageOfDeprecatedOutputs(ctx EvalContext) tfdiags.Diagnostics {
+	var diags tfdiags.Diagnostics
+
+	fmt.Printf("\n\t n.References() --> %#v \n", n.References())
+	for _, ref := range n.References() {
+		fmt.Printf("\n\t ref --> %#v \n", ref)
+		if out, ok := ref.Subject.(addrs.ModuleCallInstanceOutput); ok {
+			fmt.Printf("\n\t out --> %#v \n", out)
+
+			// TODO: Find the configuration for the output
+			// Check if the output is deprecated and emit this diagnostic
+
+			// diags = diags.Append(&hcl.Diagnostic{
+			// 			Severity: hcl.DiagWarning,
+			// 			Summary:  "Usage of deprecated output",
+			// 			Detail:   n.Config.DeprecatedMessage,
+			// 			Subject:  ref.SourceRange.ToHCL().Ptr(),
+			// 		})
+		}
+	}
+
+	return diags
+}
+
 // graphNodesAreResourceInstancesInDifferentInstancesOfSameModule is an
 // annoyingly-task-specific helper function that returns true if and only if
 // the following conditions hold:

internal/terraform/node_resource_plan.go

@@ -142,6 +142,7 @@ func (n *nodeExpandPlannableResource) DynamicExpand(ctx EvalContext) (*Graph, tf
 
 	g, expandDiags := n.dynamicExpand(ctx, moduleInstances, imports)
 	diags = diags.Append(expandDiags)
+
 	return g, diags
 }
 

internal/terraform/node_resource_plan_instance.go

@@ -70,14 +70,18 @@ var (
 func (n *NodePlannableResourceInstance) Execute(ctx EvalContext, op walkOperation) tfdiags.Diagnostics {
 	addr := n.ResourceInstanceAddr()
 
+	var diags tfdiags.Diagnostics
+	// TODO: Find better place
+	diags = diags.Append(diags, n.validateUsageOfDeprecatedOutputs(ctx))
+
 	// Eval info is different depending on what kind of resource this is
 	switch addr.Resource.Resource.Mode {
 	case addrs.ManagedResourceMode:
-		return n.managedResourceExecute(ctx)
+		return diags.Append(diags, n.managedResourceExecute(ctx))
 	case addrs.DataResourceMode:
-		return n.dataResourceExecute(ctx)
+		return diags.Append(diags, n.dataResourceExecute(ctx))
 	case addrs.EphemeralResourceMode:
-		return n.ephemeralResourceExecute(ctx)
+		return diags.Append(diags, n.ephemeralResourceExecute(ctx))
 	default:
 		panic(fmt.Errorf("unsupported resource mode %s", n.Config.Mode))
 	}

internal/terraform/node_resource_validate.go

@@ -468,6 +468,8 @@ func (n *NodeValidatableResource) validateResource(ctx EvalContext) tfdiags.Diag
 		diags = diags.Append(resp.Diagnostics.InConfigBody(n.Config.Config, n.Addr.String()))
 	}
 
+	diags = diags.Append(diags, n.validateUsageOfDeprecatedOutputs(ctx))
+
 	return diags
 }