Reinstate ghostscript/imagick install; fix bmp name in regenerate test.

.travis.yml

@@ -47,6 +47,8 @@ before_install:
     else
       echo "xdebug.ini does not exist"
     fi
+  - bash bin/install-imagick.sh
+  - php -m
 
 install:
   - composer require wp-cli/wp-cli:dev-master
@@ -58,3 +60,8 @@ before_script:
 
 script:
   - bash bin/test.sh
+
+addons:
+  apt:
+    packages:
+    - ghostscript

features/media-regenerate.feature

@@ -1233,7 +1233,7 @@ Feature: Regenerate WordPress attachments
   Scenario: Regenerate image uploaded with no sizes metadata
     Given download:
       | path                             | url                                               |
-      | {CACHE_DIR}/white-200-square.bmp | http://wp-cli.org/behat-data/white-200-square.bmp |
+      | {CACHE_DIR}/white-160-square.bmp | http://wp-cli.org/behat-data/white-160-square.bmp |
     And a wp-content/mu-plugins/media-settings.php file:
       """
       <?php
@@ -1245,6 +1245,10 @@ Feature: Regenerate WordPress attachments
           }
           return $image_editors;
       } );
+      // Enable BMP as displayable image (for WP < 4.0).
+      add_filter( 'file_is_displayable_image', function ( $result, $path ) {
+          return $result ? $result : false !== strpos( $path, '.bmp' );
+      }, 10, 2 );
       """
     And I run `wp option update uploads_use_yearmonth_folders 0`
 
@@ -1267,9 +1271,9 @@ Feature: Regenerate WordPress attachments
       """
       Success: Regenerated 0 of 1 images (1 skipped).
       """
-    And STDERR should contain:
+    And STDERR should not contain:
       """
-      Warning: No editor could be selected. (ID {BMP_ATTACHMENT_ID})
+      Warning: No editor could be selected.
       """
     And the wp-content/uploads/white-160-square-150x150.bmp file should not exist
 
@@ -1464,6 +1468,10 @@ Feature: Regenerate WordPress attachments
       """
       Error: Only regenerated 2 of 4 images (1 failed, 1 skipped).
       """
+    And STDERR should not contain:
+      """
+      Warning: No editor could be selected.
+      """
     And the return code should be 1
 
     # Make minimal pdf fail.
@@ -1513,4 +1521,8 @@ Feature: Regenerate WordPress attachments
       """
       Error: Only regenerated 1 of 4 images (2 failed, 1 skipped).
       """
+    And STDERR should not contain:
+      """
+      Warning: No editor could be selected.
+      """
     And the return code should be 1

src/Media_Command.php

@@ -654,34 +654,15 @@ private function needs_regeneration( $att_id, $fullsizepath, $is_pdf, $image_siz
 		// Assume not skipping.
 		$skip_it = false;
 
+		// Note: zero-length string returned if no metadata, for instance if PDF or non-standard image (eg an SVG).
 		$metadata = wp_get_attachment_metadata($att_id);
 
-		if ( ! is_array( $metadata ) ) {
-			if ( $is_pdf ) {
-				$editor = wp_get_image_editor( $fullsizepath );
-				$no_pdf_editor = is_wp_error( $editor );
-				unset( $editor );
-				if ( $no_pdf_editor ) {
-					// No PDF thumbnail generation available, so skip.
-					$skip_it = true;
-					return false;
-				}
-				// Assume it may be possible to regenerate the PDF thumbnails and allow processing to continue and possibly fail.
-				return true;
-			}
-			// Assume it's not a standard image (eg an SVG) and skip.
-			$skip_it = true;
-			return false;
-		}
-
-		// Note that an attachment can have no sizes if it's on or below the thumbnail threshold.
-
-		// Check whether there's new sizes or they've changed.
+		// Check whether there's new sizes or they've changed. Note that an attachment can have no sizes if it's on or below the thumbnail threshold.
 		$image_sizes = $this->get_intermediate_image_sizes_for_attachment( $fullsizepath, $is_pdf, $metadata );
 		if ( is_wp_error( $image_sizes ) ) {
 			if ( 'image_no_editor' === $image_sizes->get_error_code() ) {
-				// Warn unless PDF.
-				if ( ! $is_pdf ) {
+				// Warn unless PDF or non-standard image.
+				if ( ! $is_pdf && is_array( $metadata ) && ! empty( $metadata['sizes'] ) ) {
 					WP_CLI::warning( sprintf( '%s (ID %d)', $image_sizes->get_error_message(), $att_id ) );
 				}
 				$skip_it = true;
@@ -692,6 +673,14 @@ private function needs_regeneration( $att_id, $fullsizepath, $is_pdf, $image_siz
 			return true;
 		}
 
+		// If uploaded when applicable image editor such as Imagick unavailable, the metadata or sizes metadata may not exist.
+		if ( ! is_array( $metadata ) ) {
+			$metadata = array();
+		}
+		if ( ! isset( $metadata['sizes'] ) || ! is_array( $metadata['sizes'] ) ) {
+			$metadata['sizes'] = array();
+		}
+
 		if ( $image_size ) {
 			if ( empty( $image_sizes[ $image_size ] ) ) {
 				return false;
@@ -702,12 +691,7 @@ private function needs_regeneration( $att_id, $fullsizepath, $is_pdf, $image_siz
 			$metadata['sizes'] = array( $image_size => $metadata['sizes'][ $image_size ] );
 		}
 
-		// In certain situations, eg if file uploaded when applicable image editor such as Imagick unavailable, the sizes metadata may not exist.
-		if ( ! isset( $metadata['sizes'] ) ) {
-			$metadata['sizes'] = array();
-		}
-
-		if ( $this->image_sizes_differ( $image_sizes, (array) $metadata['sizes'] ) ) {
+		if ( $this->image_sizes_differ( $image_sizes, $metadata['sizes'] ) ) {
 			return true;
 		}
 
@@ -822,7 +806,7 @@ private function get_intermediate_sizes( $is_pdf, $metadata ) {
 			}
 		}
 
-		if ( ! $is_pdf ) {
+		if ( ! $is_pdf && is_array( $metadata ) ) {
 			$sizes = apply_filters( 'intermediate_image_sizes_advanced', $sizes, $metadata );
 		}
 

travis-append.yml

@@ -0,0 +1,5 @@
+
+addons:
+  apt:
+    packages:
+    - ghostscript

travis-before_install-append.yml

@@ -0,0 +1,2 @@
+  - bash bin/install-imagick.sh
+  - php -m