Accept optional generated config for a config directory

Author: bbasata

internal/teststep/config.go

@@ -45,6 +45,7 @@ type Config interface {
 	HasProviderBlock(context.Context) (bool, error)
 	HasTerraformBlock(context.Context) (bool, error)
 	Write(context.Context, string) error
+	AppendGeneratedConfig(context.Context, string) Config
 }
 
 // PrepareConfigurationRequest is used to simplify the generation of

internal/teststep/directory.go

@@ -5,14 +5,18 @@ package teststep
 
 import (
 	"context"
+	"fmt"
+	"hash/crc32"
 	"os"
 	"path/filepath"
 )
 
 var _ Config = configurationDirectory{}
 
+// not threadsafe
 type configurationDirectory struct {
-	directory string
+	directory      string
+	generatedFiles map[string]string
 }
 
 // HasConfigurationFiles is used during validation to ensure that
@@ -85,10 +89,43 @@ func (c configurationDirectory) Write(ctx context.Context, dest string) error {
 	}
 
 	err := copyFiles(configDirectory, dest)
+	if err != nil {
+		return err
+	}
 
+	err = c.writeGeneratedFiles(dest)
 	if err != nil {
 		return err
 	}
 
 	return nil
 }
+
+func (c configurationDirectory) AppendGeneratedConfig(_ context.Context, config string) Config {
+	if c.generatedFiles == nil {
+		c.generatedFiles = make(map[string]string)
+	}
+
+	checksum := crc32.Checksum([]byte(config), crc32.IEEETable)
+	filename := fmt.Sprintf("terraform_plugin_test_%d.tf", checksum)
+
+	fmt.Println("Appending generated file:", filename)
+	c.generatedFiles[filename] = config
+	return c
+}
+
+func (c configurationDirectory) writeGeneratedFiles(dstPath string) error {
+	fmt.Println("Count of generated files:", len(c.generatedFiles))
+	for filename, config := range c.generatedFiles {
+		outFilename := filepath.Join(dstPath, filename)
+		fmt.Println("Writing generated file:", outFilename)
+
+		err := os.WriteFile(outFilename, []byte(config), 0700)
+		if err != nil {
+			return err
+		}
+		fmt.Println("Wrote generated file:", outFilename)
+	}
+
+	return nil
+}

internal/teststep/directory_test.go

@@ -607,6 +607,81 @@ func TestConfigurationDirectory_Write_AbsolutePath(t *testing.T) {
 	}
 }
 
+func TestConfigurationDirectory_Write_WithGeneratedFiles(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		configDirectory configurationDirectory
+		expectedError   *regexp.Regexp
+	}{
+		"dir-single-file": {
+			configDirectory: configurationDirectory{
+				directory: "testdata/random",
+				generatedFiles: map[string]string{
+					"import.tf": `terraform {\nimport\n{\nto = satellite.the_moon\nid = "moon"\n}\n}\n`,
+				},
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			tempDir := t.TempDir()
+
+			err := testCase.configDirectory.Write(context.Background(), tempDir)
+			if err != nil {
+				t.Errorf("unexpected error %s", err)
+			}
+
+			dirEntries, err := os.ReadDir(testCase.configDirectory.directory)
+			if err != nil {
+				t.Errorf("error reading directory: %s", err)
+			}
+
+			tempDirEntries, err := os.ReadDir(tempDir)
+
+			if err != nil {
+				t.Errorf("error reading temp directory: %s", err)
+			}
+
+			if len(tempDirEntries)-len(dirEntries) != 1 {
+				t.Errorf("expected %d dir entries, got %d dir entries", len(dirEntries)+1, tempDirEntries)
+			}
+
+			for _, entry := range dirEntries {
+				filename := entry.Name()
+				expectedContent, err := os.ReadFile(filepath.Join(testCase.configDirectory.directory, filename))
+				if err != nil {
+					t.Errorf("error reading file from config directory %s: %s", filename, err)
+				}
+
+				content, err := os.ReadFile(filepath.Join(tempDir, filename))
+				if err != nil {
+					t.Errorf("error reading generated file %s: %s", filename, err)
+				}
+
+				if diff := cmp.Diff(expectedContent, content); diff != "" {
+					t.Errorf("unexpected difference: %s", diff)
+				}
+			}
+
+			generatedFiles := testCase.configDirectory.generatedFiles
+			for filename, expectedContent := range generatedFiles {
+				content, err := os.ReadFile(filepath.Join(tempDir, filename))
+				if err != nil {
+					t.Errorf("error reading generated file %s: %s", filename, err)
+				}
+
+				if diff := cmp.Diff([]byte(expectedContent), content); diff != "" {
+					t.Errorf("unexpected difference: %s", diff)
+				}
+			}
+		})
+	}
+}
+
 var fileInfoComparer = cmp.Comparer(func(x, y os.FileInfo) bool {
 	if x.Name() != y.Name() {
 		return false

internal/teststep/file.go

@@ -92,3 +92,7 @@ func (c configurationFile) Write(ctx context.Context, dest string) error {
 
 	return nil
 }
+
+func (c configurationFile) AppendGeneratedConfig(_ context.Context, config string) Config {
+	return c
+}

internal/teststep/string.go

@@ -57,5 +57,11 @@ func (c configurationString) Write(ctx context.Context, dest string) error {
 		return err
 	}
 
+	fmt.Println("Wrote config to", outFilename)
+
 	return nil
 }
+
+func (c configurationString) AppendGeneratedConfig(_ context.Context, config string) Config {
+	return c
+}