Fix no-op outputs causing the plan renderer to skip the 'no changes' message (#32820)

* Fix no-op outputs causing the plan renderer to skip the 'no changes' message

* fix imports

Author: Liam Cervante

internal/command/jsonformat/plan.go

@@ -84,7 +84,11 @@ func (plan Plan) renderHuman(renderer Renderer, mode plans.Mode, opts ...PlanRen
 		}
 	}
 
-	if len(changes) == 0 && len(diffs.outputs) == 0 {
+	// Precompute the outputs early, so we can make a decision about whether we
+	// display the "there are no changes messages".
+	outputs := renderHumanDiffOutputs(renderer, diffs.outputs)
+
+	if len(changes) == 0 && len(outputs) == 0 {
 		// If we didn't find any changes to report at all then this is a
 		// "No changes" plan. How we'll present this depends on whether
 		// the plan is "applyable" and, if so, whether it had refresh changes
@@ -219,10 +223,9 @@ func (plan Plan) renderHuman(renderer Renderer, mode plans.Mode, opts ...PlanRen
 			counts[plans.Delete]+counts[plans.DeleteThenCreate]+counts[plans.CreateThenDelete])
 	}
 
-	diff := renderHumanDiffOutputs(renderer, diffs.outputs)
-	if len(diff) > 0 {
+	if len(outputs) > 0 {
 		renderer.Streams.Print("\nChanges to Outputs:\n")
-		renderer.Streams.Printf("%s\n", diff)
+		renderer.Streams.Printf("%s\n", outputs)
 
 		if len(counts) == 0 {
 			// If we have output changes but not resource changes then we

internal/command/jsonformat/plan_test.go

@@ -1,27 +1,81 @@
 package jsonformat
 
 import (
+	"encoding/json"
 	"fmt"
 	"testing"
 
-	"github.com/hashicorp/terraform/internal/command/jsonformat/differ/attribute_path"
-
 	"github.com/google/go-cmp/cmp"
 	"github.com/mitchellh/colorstring"
 	"github.com/zclconf/go-cty/cty"
 
 	"github.com/hashicorp/terraform/internal/addrs"
 	"github.com/hashicorp/terraform/internal/command/jsonformat/differ"
+	"github.com/hashicorp/terraform/internal/command/jsonformat/differ/attribute_path"
 	"github.com/hashicorp/terraform/internal/command/jsonplan"
 	"github.com/hashicorp/terraform/internal/command/jsonprovider"
 	"github.com/hashicorp/terraform/internal/configs/configschema"
 	"github.com/hashicorp/terraform/internal/lang/marks"
 	"github.com/hashicorp/terraform/internal/plans"
 	"github.com/hashicorp/terraform/internal/providers"
 	"github.com/hashicorp/terraform/internal/states"
+	"github.com/hashicorp/terraform/internal/terminal"
 	"github.com/hashicorp/terraform/internal/terraform"
 )
 
+func TestRenderHuman_EmptyPlan(t *testing.T) {
+	color := &colorstring.Colorize{Colors: colorstring.DefaultColors, Disable: true}
+	streams, done := terminal.StreamsForTesting(t)
+
+	plan := Plan{}
+
+	renderer := Renderer{Colorize: color, Streams: streams}
+	plan.renderHuman(renderer, plans.NormalMode)
+
+	want := `
+No changes. Your infrastructure matches the configuration.
+
+Terraform has compared your real infrastructure against your configuration
+and found no differences, so no changes are needed.
+`
+
+	got := done(t).Stdout()
+	if diff := cmp.Diff(want, got); len(diff) > 0 {
+		t.Errorf("unexpected output\ngot:\n%s\nwant:\n%s\ndiff:\n%s", got, want, diff)
+	}
+}
+
+func TestRenderHuman_EmptyOutputs(t *testing.T) {
+	color := &colorstring.Colorize{Colors: colorstring.DefaultColors, Disable: true}
+	streams, done := terminal.StreamsForTesting(t)
+
+	outputVal, _ := json.Marshal("some-text")
+	plan := Plan{
+		OutputChanges: map[string]jsonplan.Change{
+			"a_string": {
+				Actions: []string{"no-op"},
+				Before:  outputVal,
+				After:   outputVal,
+			},
+		},
+	}
+
+	renderer := Renderer{Colorize: color, Streams: streams}
+	plan.renderHuman(renderer, plans.NormalMode)
+
+	want := `
+No changes. Your infrastructure matches the configuration.
+
+Terraform has compared your real infrastructure against your configuration
+and found no differences, so no changes are needed.
+`
+
+	got := done(t).Stdout()
+	if diff := cmp.Diff(want, got); len(diff) > 0 {
+		t.Errorf("unexpected output\ngot:\n%s\nwant:\n%s\ndiff:\n%s", got, want, diff)
+	}
+}
+
 func TestResourceChange_primitiveTypes(t *testing.T) {
 	testCases := map[string]testCase{
 		"creation": {