Add a test for examples replacement

pkg/tfgen/docs.go

@@ -491,6 +491,10 @@ type tfMarkdownParser struct {
 	editRules editRules
 
 	ret entityDocs
+
+	// readFile allows tests to mock out external files. It should not be set outside
+	// of test cases.
+	readFileFunc func(string) ([]byte, error)
 }
 
 const (
@@ -502,13 +506,22 @@ const (
 	sectionImports             = 5
 )
 
-func (p *tfMarkdownParser) parseSupplementaryExamples() (string, error) {
+func (p *tfMarkdownParser) readFile(name string) ([]byte, error) {
+	if p.readFileFunc != nil {
+		// p.readFileFunc is a testing hard-point. Outside of tests,
+		// p.readFileFunc should be nil.
+		return p.readFileFunc(name)
+	}
+	return os.ReadFile(name)
+}
+
+func (p *tfMarkdownParser) readSupplementaryExamples() (string, error) {
 	examplesFileName := fmt.Sprintf("docs/%s/%s.examples.md", p.kind, p.rawname)
 	absPath, err := filepath.Abs(examplesFileName)
 	if err != nil {
 		return "", err
 	}
-	fileBytes, err := os.ReadFile(absPath)
+	fileBytes, err := p.readFile(absPath)
 	if err != nil {
 		p.sink.error("explicitly marked resource documentation for replacement, but found no file at %q", examplesFileName)
 		return "", err
@@ -550,7 +563,7 @@ func (p *tfMarkdownParser) parse(tfMarkdown []byte) (entityDocs, error) {
 		}
 
 		// now we are going to inject the new source of examples
-		newExamples, err := p.parseSupplementaryExamples()
+		newExamples, err := p.readSupplementaryExamples()
 		if err != nil {
 			return entityDocs{}, err
 		}

pkg/tfgen/docs_test.go

@@ -24,6 +24,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"strings"
 	"testing"
 	"text/template"
 
@@ -2137,6 +2138,8 @@ func TestParseTFMarkdown(t *testing.T) {
 		rawName      string
 
 		fileName string
+
+		readFileFunc func(string) ([]byte, error)
 	}
 
 	// Assert that file contents match the expected description.
@@ -2182,6 +2185,24 @@ func TestParseTFMarkdown(t *testing.T) {
 					[]byte(`checking custom replaces`)), nil
 			})),
 		test("codeblock-header"),
+		test("replace-examples",
+			func(tc *testCase) {
+				tc.readFileFunc = func(name string) ([]byte, error) {
+					switch {
+					// This test works on windows if and only if we use the correct separator.
+					case strings.HasSuffix(name, filepath.Join("docs", "resource", "pkg_mod1_res1.examples.md")):
+						return []byte(`## REPLACEMENT TEXT
+This should be interpolated in.
+`), nil
+					default:
+						return nil, fmt.Errorf("invalid path %q", name)
+					}
+
+				}
+				tc.info = &tfbridge.ResourceInfo{Docs: &tfbridge.DocInfo{
+					ReplaceExamplesSection: true,
+				}}
+			}),
 	}
 
 	for _, tt := range tests {
@@ -2203,7 +2224,8 @@ func TestParseTFMarkdown(t *testing.T) {
 					pkg:      "pkg",
 					info:     tt.providerInfo,
 				},
-				editRules: getEditRules(tt.providerInfo.DocRules),
+				editRules:    getEditRules(tt.providerInfo.DocRules),
+				readFileFunc: tt.readFileFunc,
 			}
 
 			inputBytes, err := os.ReadFile(input)
@@ -2346,7 +2368,7 @@ func (r *mockResource) GetFields() map[string]*tfbridge.SchemaInfo {
 }
 
 func (r *mockResource) ReplaceExamplesSection() bool {
-	return false
+	return r.docs.ReplaceExamplesSection
 }
 
 func (r *mockResource) GetDocs() *tfbridge.DocInfo {

pkg/tfgen/test_data/replace-examples/expected.json

@@ -0,0 +1,6 @@
+{
+  "Description": "main body\n\n## Some other section\n\nother body\n\n## REPLACEMENT TEXT\n\nThis should be interpolated in.",
+  "Arguments": {},
+  "Attributes": {},
+  "Import": ""
+}

pkg/tfgen/test_data/replace-examples/input.md

@@ -0,0 +1,26 @@
+---
+page_title: "test_replace_examples Resource - terraform-provider-test"
+description: |-
+  Validate that we can replace examples correctly.
+---
+
+# test_replace_examples (Resource)
+
+main body
+
+## Example Usage
+
+Should be skipped
+
+```terraform
+## Minimal
+resource "snowflake_database" "primary" {
+  name = "database_name"
+}
+```
+
+## Some other section
+
+other body
+
+## Example Usage - also replaced