fix: rewrite onlyDataResources (#9263)

provisioner/terraform/executor.go

@@ -264,18 +264,21 @@ func (e *executor) plan(ctx, killCtx context.Context, env, vars []string, logr l
 	}, nil
 }
 
-func onlyDataResources(sm *tfjson.StateModule) *tfjson.StateModule {
+func onlyDataResources(sm tfjson.StateModule) tfjson.StateModule {
-	sm2 := *sm
+	filtered := sm
-	sm2.Resources = make([]*tfjson.StateResource, 0, len(sm.Resources))
+	filtered.Resources = []*tfjson.StateResource{}
 	for _, r := range sm.Resources {
 		if r.Mode == "data" {
-			sm2.Resources = append(sm2.Resources, r)
+			filtered.Resources = append(filtered.Resources, r)
 		}
 	}
+
+	filtered.ChildModules = []*tfjson.StateModule{}
 	for _, c := range sm.ChildModules {
-		sm2.ChildModules = append(sm2.ChildModules, onlyDataResources(c))
+		filteredChild := onlyDataResources(*c)
+		filtered.ChildModules = append(filtered.ChildModules, &filteredChild)
 	}
-	return &sm2
+	return filtered
 }
 
 // planResources must only be called while the lock is held.
@@ -300,10 +303,9 @@ func (e *executor) planResources(ctx, killCtx context.Context, planfilePath stri
 		// We don't want all prior resources, because Quotas (and
 		// future features) would never know which resources are getting
 		// deleted by a stop.
-		modules = append(
+
-			modules,
+		filtered := onlyDataResources(*plan.PriorState.Values.RootModule)
-			onlyDataResources(plan.PriorState.Values.RootModule),
+		modules = append(modules, &filtered)
-		)
 	}
 	modules = append(modules, plan.PlannedValues.RootModule)
 

provisioner/terraform/executor_internal_test.go

@@ -1,8 +1,10 @@
 package terraform
 
 import (
+	"encoding/json"
 	"testing"
 
+	tfjson "github.com/hashicorp/terraform-json"
 	"github.com/stretchr/testify/require"
 
 	"github.com/coder/coder/v2/provisionersdk/proto"
@@ -41,3 +43,133 @@ From standing in the English rain`))
 	}
 	require.Equal(t, expected, logr.logs)
 }
+
+func TestOnlyDataResources(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name     string
+		stateMod *tfjson.StateModule
+		expected *tfjson.StateModule
+	}{
+		{
+			name:     "empty state module",
+			stateMod: &tfjson.StateModule{},
+			expected: &tfjson.StateModule{},
+		},
+		{
+			name: "only data resources",
+			stateMod: &tfjson.StateModule{
+				Resources: []*tfjson.StateResource{
+					{Name: "cat", Type: "coder_parameter", Mode: "data", Address: "cat-address"},
+					{Name: "cow", Type: "foobaz", Mode: "data", Address: "cow-address"},
+				},
+				ChildModules: []*tfjson.StateModule{
+					{
+						Resources: []*tfjson.StateResource{
+							{Name: "child-cat", Type: "coder_parameter", Mode: "data", Address: "child-cat-address"},
+							{Name: "child-dog", Type: "foobar", Mode: "data", Address: "child-dog-address"},
+						},
+						Address: "child-module-1",
+					},
+				},
+				Address: "fake-module",
+			},
+			expected: &tfjson.StateModule{
+				Resources: []*tfjson.StateResource{
+					{Name: "cat", Type: "coder_parameter", Mode: "data", Address: "cat-address"},
+					{Name: "cow", Type: "foobaz", Mode: "data", Address: "cow-address"},
+				},
+				ChildModules: []*tfjson.StateModule{
+					{
+						Resources: []*tfjson.StateResource{
+							{Name: "child-cat", Type: "coder_parameter", Mode: "data", Address: "child-cat-address"},
+							{Name: "child-dog", Type: "foobar", Mode: "data", Address: "child-dog-address"},
+						},
+						Address: "child-module-1",
+					},
+				},
+				Address: "fake-module",
+			},
+		},
+		{
+			name: "only non-data resources",
+			stateMod: &tfjson.StateModule{
+				Resources: []*tfjson.StateResource{
+					{Name: "cat", Type: "coder_parameter", Mode: "foobar", Address: "cat-address"},
+					{Name: "cow", Type: "foobaz", Mode: "foo", Address: "cow-address"},
+				},
+				ChildModules: []*tfjson.StateModule{
+					{
+						Resources: []*tfjson.StateResource{
+							{Name: "child-cat", Type: "coder_parameter", Mode: "foobar", Address: "child-cat-address"},
+							{Name: "child-dog", Type: "foobar", Mode: "foobaz", Address: "child-dog-address"},
+						},
+						Address: "child-module-1",
+					},
+				},
+				Address: "fake-module",
+			},
+			expected: &tfjson.StateModule{
+				Address: "fake-module",
+				ChildModules: []*tfjson.StateModule{
+					{Address: "child-module-1"},
+				},
+			},
+		},
+		{
+			name: "mixed resources",
+			stateMod: &tfjson.StateModule{
+				Resources: []*tfjson.StateResource{
+					{Name: "cat", Type: "coder_parameter", Mode: "data", Address: "cat-address"},
+					{Name: "dog", Type: "foobar", Mode: "magic", Address: "dog-address"},
+					{Name: "cow", Type: "foobaz", Mode: "data", Address: "cow-address"},
+				},
+				ChildModules: []*tfjson.StateModule{
+					{
+						Resources: []*tfjson.StateResource{
+							{Name: "child-cat", Type: "coder_parameter", Mode: "data", Address: "child-cat-address"},
+							{Name: "child-dog", Type: "foobar", Mode: "data", Address: "child-dog-address"},
+							{Name: "child-cow", Type: "foobaz", Mode: "magic", Address: "child-cow-address"},
+						},
+						Address: "child-module-1",
+					},
+				},
+				Address: "fake-module",
+			},
+			expected: &tfjson.StateModule{
+				Resources: []*tfjson.StateResource{
+					{Name: "cat", Type: "coder_parameter", Mode: "data", Address: "cat-address"},
+					{Name: "cow", Type: "foobaz", Mode: "data", Address: "cow-address"},
+				},
+				ChildModules: []*tfjson.StateModule{
+					{
+						Resources: []*tfjson.StateResource{
+							{Name: "child-cat", Type: "coder_parameter", Mode: "data", Address: "child-cat-address"},
+							{Name: "child-dog", Type: "foobar", Mode: "data", Address: "child-dog-address"},
+						},
+						Address: "child-module-1",
+					},
+				},
+				Address: "fake-module",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			filtered := onlyDataResources(*tt.stateMod)
+
+			expected, err := json.Marshal(tt.expected)
+			require.NoError(t, err)
+			got, err := json.Marshal(filtered)
+			require.NoError(t, err)
+
+			require.Equal(t, string(expected), string(got))
+		})
+	}
+}