Return a value from processContentType instead of modifying the existing status

Fixes an issue that was caught by the test I just added - the recorded edit would be marked with the *new* content type instead of the old one, which is obviously bad

internal/processing/status/common.go

@@ -110,7 +110,7 @@ func (p *Processor) processContent(
 	ctx context.Context,
 	author *gtsmodel.Account,
 	statusID string,
-	contentType apimodel.StatusContentType,
+	contentType gtsmodel.StatusContentType,
 	content string,
 	contentWarning string,
 	language string,
@@ -149,11 +149,11 @@ func (p *Processor) processContent(
 	switch contentType {
 
 	// Format status according to text/plain.
-	case apimodel.StatusContentTypePlain:
+	case gtsmodel.StatusContentTypePlain:
 		format = p.formatter.FromPlain
 
 	// Format status according to text/markdown.
-	case apimodel.StatusContentTypeMarkdown:
+	case gtsmodel.StatusContentTypeMarkdown:
 		format = p.formatter.FromMarkdown
 
 	// Unknown.

internal/processing/status/create.go

@@ -81,7 +81,7 @@ func (p *Processor) Create(
 	content, errWithCode := p.processContent(ctx,
 		requester,
 		statusID,
-		contentType,
+		typeutils.APIContentTypeToContentType(contentType),
 		form.Status,
 		form.SpoilerText,
 		form.Language,

internal/processing/status/edit.go

@@ -85,14 +85,14 @@ func (p *Processor) Edit(
 		return nil, errWithCode
 	}
 
-	// Process incoming content type and update as needed
+	// Process incoming content type
-	p.processContentType(ctx, form, status, requester.Settings.StatusContentType)
+	contentType := p.processContentType(ctx, form, status, requester.Settings.StatusContentType)
 
 	// Process incoming status edit content fields.
 	content, errWithCode := p.processContent(ctx,
 		requester,
 		statusID,
-		form.ContentType,
+		contentType,
 		form.Status,
 		form.SpoilerText,
 		form.Language,
@@ -303,7 +303,7 @@ func (p *Processor) Edit(
 	status.Content = content.Content
 	status.ContentWarning = content.ContentWarning
 	status.Text = form.Status
-	status.ContentType = typeutils.APIContentTypeToContentType(form.ContentType)
+	status.ContentType = contentType
 	status.Language = content.Language
 	status.Sensitive = &form.Sensitive
 	status.AttachmentIDs = form.MediaIDs
@@ -348,34 +348,30 @@ func (p *Processor) Edit(
 	return p.c.GetAPIStatus(ctx, requester, status)
 }
 
-// Updates the content type of the status
+// Returns the new content type of the status when applying an edit.
 func (p *Processor) processContentType(
 	ctx context.Context,
 	form *apimodel.StatusEditRequest,
 	status *gtsmodel.Status,
 	accountDefaultContentType string,
-) {
+) gtsmodel.StatusContentType {
 	switch {
-	// Content type set on form, update the status with the new value.
+	// Content type set on form, return the new value.
 	case form.ContentType != "":
-		status.ContentType = typeutils.APIContentTypeToContentType(form.ContentType)
+		return typeutils.APIContentTypeToContentType(form.ContentType)
 
-	// No content type on the form, get the status's current content type and
+	// No content type on the form, return the status's current content type.
-	// set it back on the form for later use.
 	case status.ContentType != 0:
-		form.ContentType = p.converter.ContentTypeToAPIContentType(ctx, status.ContentType)
+		return status.ContentType
 
-	// Old statuses may not have a saved content type; update the status to the
+	// Old statuses may not have a saved content type;
-	// user's preference and set this back on the form for later use.
+	// return the user's default content type preference.
 	case accountDefaultContentType != "":
-		status.ContentType = typeutils.APIContentTypeToContentType(apimodel.StatusContentType(accountDefaultContentType))
+		return typeutils.APIContentTypeToContentType(apimodel.StatusContentType(accountDefaultContentType))
-		form.ContentType = apimodel.StatusContentType(accountDefaultContentType)
 
-	// uhh.. Fall back to global default, set
+	// uhh.. Fall back to global default.
-	// this back on the form for later use.
 	default:
-		status.ContentType = gtsmodel.StatusContentTypeDefault
+		return gtsmodel.StatusContentTypeDefault
-		form.ContentType = apimodel.StatusContentTypeDefault
 	}
 }