[#756] Made accessibility console summary opt-in via 'BEHAT_ACCESSIBILITY_PRINT'.

STEPS.md

@@ -91,6 +91,11 @@
 >  file is written per run, so a run never overwrites a previous one. The
 >  aggregate accumulates in process-global state, so under parallel Behat each
 >  process writes its own report.
+>  <br/><br/>
+>  Console output. A one-line per-page summary can be printed to the console
+>  as pages are assessed. Printing is off by default; set the
+>  `BEHAT_ACCESSIBILITY_PRINT` environment variable to a non-empty value other
+>  than `0`, or override `accessibilityGetPrintCli()`, to enable it.
 
 
 <details>

src/AccessibilityTrait.php

@@ -41,6 +41,11 @@
  * file is written per run, so a run never overwrites a previous one. The
  * aggregate accumulates in process-global state, so under parallel Behat each
  * process writes its own report.
+ *
+ * Console output. A one-line per-page summary can be printed to the console
+ * as pages are assessed. Printing is off by default; set the
+ * `BEHAT_ACCESSIBILITY_PRINT` environment variable to a non-empty value other
+ * than `0`, or override `accessibilityGetPrintCli()`, to enable it.
  */
 trait AccessibilityTrait {
 
@@ -459,6 +464,19 @@ protected function accessibilityGetFailOnIncomplete(): bool {
     return FALSE;
   }
 
+  /**
+   * Return TRUE to print a one-line per-page summary to the console.
+   *
+   * Default: enabled only when the `BEHAT_ACCESSIBILITY_PRINT` environment
+   * variable is set to a non-empty value other than `0`. Override to
+   * hardcode either behaviour.
+   */
+  protected function accessibilityGetPrintCli(): bool {
+    $value = getenv('BEHAT_ACCESSIBILITY_PRINT');
+
+    return !in_array($value, [FALSE, '', '0'], TRUE);
+  }
+
   /**
    * Return the canonical impact levels in descending severity order.
    *
@@ -709,13 +727,15 @@ protected function accessibilityAssess(string $rules): array {
     $this->accessibilityResults[] = ['url' => $url, 'rules' => $rules, 'result' => $normalized];
     $this->accessibilityLastCheckedUrl = $url;
 
-    fwrite(STDOUT, sprintf("\n[accessibility] %s: %d violations, %d passes, %d incomplete (rules: %s)\n",
-      $this->accessibilityFormatUrl($url),
-      count($normalized['violations'] ?? []),
-      count($normalized['passes'] ?? []),
-      count($normalized['incomplete'] ?? []),
-      $rules
-    ));
+    if ($this->accessibilityGetPrintCli()) {
+      fwrite(STDOUT, sprintf("\n[accessibility] %s: %d violations, %d passes, %d incomplete (rules: %s)\n",
+        $this->accessibilityFormatUrl($url),
+        count($normalized['violations'] ?? []),
+        count($normalized['passes'] ?? []),
+        count($normalized['incomplete'] ?? []),
+        $rules
+      ));
+    }
 
     return $normalized;
   }

tests/behat/features/accessibility.feature

@@ -123,3 +123,34 @@ Feature: Check that AccessibilityTrait works
       """
       <system-out>
       """
+
+  @trait:AccessibilityTrait
+  Scenario: Console summary is not printed by default
+    Given some behat configuration
+    And scenario steps tagged with "@javascript @phpserver":
+      """
+      Given I visit "http://cli:8888/accessibility_clean.html"
+      Then the current page should pass accessibility checks
+      """
+    When I run "behat --no-colors"
+    Then it should pass
+    And the output should not contain:
+      """
+      [accessibility]
+      """
+
+  @trait:AccessibilityTrait
+  Scenario: Console summary is printed when the environment variable is set
+    Given some behat configuration
+    And scenario steps tagged with "@javascript @phpserver":
+      """
+      Given I visit "http://cli:8888/accessibility_clean.html"
+      Then the current page should pass accessibility checks
+      """
+    When the "BEHAT_ACCESSIBILITY_PRINT" environment variable is set to "1"
+    And I run "behat --no-colors"
+    Then it should pass
+    And the output should contain:
+      """
+      [accessibility] http://cli:8888/accessibility_clean.html: 0 violations,
+      """