[Fix] Ignore presence or absence of /Workspace prefix for dashboard…

… resource (#4061)

## Changes

Users may choose to include the `/Workspace` prefix in the `parent_path`
attribute of a dashboard to unambiguously refer to the workspace file
system. This prefix is not included in reads, triggering a recreate.

This change ignores this type of diff.

## Tests

- [x] `make test` run locally
- [ ] relevant change in `docs/` folder
- [x] covered with integration tests in `internal/acceptance`
- [x] relevant acceptance tests are passing
- [ ] using Go SDK

common/resource.go

@@ -440,6 +440,16 @@ func genericDatabricksData[T, P, C any](
 	}
 }
 
+// WorkspacePathPrefixDiffSuppress suppresses diffs for workspace paths where both sides
+// may or may not include the `/Workspace` prefix.
+//
+// This is the case for dashboards where at create time, the user may include the `/Workspace`
+// prefix for the `parent_path` field, but the read response will not include the prefix.
+func WorkspacePathPrefixDiffSuppress(k, old, new string, d *schema.ResourceData) bool {
+	const prefix = "/Workspace"
+	return strings.TrimPrefix(old, prefix) == strings.TrimPrefix(new, prefix)
+}
+
 func EqualFoldDiffSuppress(k, old, new string, d *schema.ResourceData) bool {
 	if strings.EqualFold(old, new) {
 		log.Printf("[INFO] Suppressing diff on %s", k)

common/resource_test.go

@@ -179,6 +179,14 @@ func TestCustomizeDiffRobustness(t *testing.T) {
 	assert.EqualError(t, err, "cannot customize diff for sample: panic: oops")
 }
 
+func TestWorkspacePathPrefixDiffSuppress(t *testing.T) {
+	assert.True(t, WorkspacePathPrefixDiffSuppress("k", "/Workspace/foo/bar", "/Workspace/foo/bar", nil))
+	assert.True(t, WorkspacePathPrefixDiffSuppress("k", "/Workspace/foo/bar", "/foo/bar", nil))
+	assert.True(t, WorkspacePathPrefixDiffSuppress("k", "/foo/bar", "/Workspace/foo/bar", nil))
+	assert.True(t, WorkspacePathPrefixDiffSuppress("k", "/foo/bar", "/foo/bar", nil))
+	assert.False(t, WorkspacePathPrefixDiffSuppress("k", "/Workspace/1", "/Workspace/2", nil))
+}
+
 func TestEqualFoldDiffSuppress(t *testing.T) {
 	assert.True(t, EqualFoldDiffSuppress("k", "A", "a", nil))
 	assert.False(t, EqualFoldDiffSuppress("k", "A", "A2", nil))

dashboards/resource_dashboard.go

@@ -42,7 +42,7 @@ func (Dashboard) CustomizeSchema(s *common.CustomizableSchema) *common.Customiza
 	s.SchemaPath("md5").SetComputed()
 
 	// ForceNew fields
-	s.SchemaPath("parent_path").SetForceNew()
+	s.SchemaPath("parent_path").SetCustomSuppressDiff(common.WorkspacePathPrefixDiffSuppress).SetForceNew()
 
 	// ConflictsWith fields
 	s.SchemaPath("serialized_dashboard").SetConflictsWith([]string{"file_path"})

internal/acceptance/dashboard_test.go

@@ -58,7 +58,7 @@ resource "databricks_permissions" "dashboard_usage" {
 	return templateString
 }
 
-// Altough EmbedCredentials is an optional field, please specify its value if you want to modify it.
+// Although EmbedCredentials is an optional field, please specify its value if you want to modify it.
 func (t *templateStruct) SetAttributes(mapper map[string]string) templateStruct {
 	// Switch case for each attribute. If it is set in the mapper, set it in the struct
 	if val, ok := mapper["display_name"]; ok {
@@ -491,3 +491,19 @@ func TestAccDashboardTestAll(t *testing.T) {
 		}),
 	})
 }
+
+func TestAccDashboardWithWorkspacePrefix(t *testing.T) {
+	var template templateStruct
+
+	// Test that the dashboard can use a /Workspace prefix on the parent path and not trigger recreation.
+	// If this does NOT work, the test fails with an error that the non-refresh plan is non-empty.
+
+	WorkspaceLevel(t, Step{
+		Template: makeTemplate(template.SetAttributes(map[string]string{
+			"display_name":         fmt.Sprintf("Test Dashboard - %s", qa.RandomName()),
+			"warehouse_id":         "{env.TEST_DEFAULT_WAREHOUSE_ID}",
+			"parent_path":          "/Workspace/Shared/provider-test",
+			"serialized_dashboard": `{\"pages\":[{\"name\":\"new_name\",\"displayName\":\"New Page\"}]}`,
+		})),
+	})
+}