From be03f3598c7eb640e74312a639a4fa860b6ec695 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adri=C3=A1n=20Bolonio?= <bolonio@github.com>
Date: Tue, 19 Jul 2022 12:00:06 +0000
Subject: [PATCH 1/2] Add new linter rule: LinkHasHref

---
 README.md                                     |  3 ++
 docs/rules/accessibility/link-has-href.md     | 25 +++++++++++++++
 .../github/accessibility/link_has_href.rb     | 32 +++++++++++++++++++
 .../accessibility/link_has_href_test.rb       | 23 +++++++++++++
 4 files changed, 83 insertions(+)
 create mode 100644 docs/rules/accessibility/link-has-href.md
 create mode 100644 lib/erblint-github/linters/github/accessibility/link_has_href.rb
 create mode 100644 test/linters/accessibility/link_has_href_test.rb

diff --git a/README.md b/README.md
index df80e45..2febb2a 100644
--- a/README.md
+++ b/README.md
@@ -31,6 +31,8 @@ linters:
     enabled: true
   GitHub::Accessibility::ImageHasAlt:
     enabled: true
+  GitHub::Accessibility::LinkHasHref:
+    enabled: true
   GitHub::Accessibility::NoAriaLabelMisuseCounter:
     enabled: true
   GitHub::Accessibility::NoPositiveTabIndex:
@@ -47,6 +49,7 @@ linters:
 - [GitHub::Accessibility::AvoidGenericLinkTextCounter](./docs/rules/accessibility/avoid-generic-link-text-counter.md)
 - [GitHub::Accessibility::IframeHasTitle](./docs/rules/accessibility/iframe-has-title.md)
 - [GitHub::Accessibility::ImageHasAlt](./docs/rules/accessibility/image-has-alt.md)
+- [GitHub::Accessibility::LinkHasHref](./docs/rules/accessibility/link_has_href.md)
 - [GitHub::Accessibility::NoAriaLabelMisuseCounter](./docs/rules/accessibility/no-aria-label-misuse-counter.md)
 - [GitHub::Accessibility::NoPositiveTabIndex](./docs/rules/accessibility/no-positive-tab-index.md)
 - [GitHub::Accessibility::NoRedundantImageAlt](./docs/rules/accessibility/no-redundant-image-alt.md)
diff --git a/docs/rules/accessibility/link-has-href.md b/docs/rules/accessibility/link-has-href.md
new file mode 100644
index 0000000..e172bc5
--- /dev/null
+++ b/docs/rules/accessibility/link-has-href.md
@@ -0,0 +1,25 @@
+# Link Has Href
+
+## Rule Details
+
+Links should go somewhere, you probably want to use a `<button>` instead.
+
+## Resources
+
+- [`<a>`: The Anchor element](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a)
+- [Primer: Links](https://primer.style/design/accessibility/links)
+
+## Examples
+### **Incorrect** code for this rule 👎
+
+```erb
+<!-- incorrect -->
+<a>Go to GitHub</a>
+```
+
+### **Correct** code for this rule  👍
+
+```erb
+<!-- correct -->
+<a href='https://github.com/'>Go to GitHub</a>
+```
\ No newline at end of file
diff --git a/lib/erblint-github/linters/github/accessibility/link_has_href.rb b/lib/erblint-github/linters/github/accessibility/link_has_href.rb
new file mode 100644
index 0000000..dc21fbb
--- /dev/null
+++ b/lib/erblint-github/linters/github/accessibility/link_has_href.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require_relative "../../custom_helpers"
+
+module ERBLint
+  module Linters
+    module GitHub
+      module Accessibility
+        class LinkHasHref < Linter
+          include ERBLint::Linters::CustomHelpers
+          include LinterRegistry
+
+          MESSAGE = "Links should go somewhere, you probably want to use a <button> instead."
+
+          def run(processed_source)
+            tags(processed_source).each do |tag|
+              next if tag.name != "a"
+              next if tag.closing?
+
+              href = possible_attribute_values(tag, "href")
+              name = tag.attributes["name"]
+
+              generate_offense(self.class, processed_source, tag) if (!name && href.empty?) || href.include?("#")
+            end
+
+            rule_disabled?(processed_source)
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/test/linters/accessibility/link_has_href_test.rb b/test/linters/accessibility/link_has_href_test.rb
new file mode 100644
index 0000000..6251db1
--- /dev/null
+++ b/test/linters/accessibility/link_has_href_test.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class LinkHasHref < LinterTestCase
+  def linter_class
+    ERBLint::Linters::GitHub::Accessibility::LinkHasHref
+  end
+
+  def test_warns_if_link_has_no_href_attribute
+    @file = "<a>Go to GitHub</a>"
+    @linter.run(processed_source)
+
+    refute_empty @linter.offenses
+  end
+
+  def test_does_not_warn_if_link_has_href_attribute
+    @file = "<a href='https://github.com/'>Go to GitHub</a>"
+    @linter.run(processed_source)
+
+    assert_empty @linter.offenses
+  end
+end

From 8f967fa621891a33b9ee866ae2c2ff596fc84c83 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adri=C3=A1n=20Bolonio?= <bolonio@github.com>
Date: Thu, 21 Jul 2022 09:44:25 +0000
Subject: [PATCH 2/2] Update linter rule LinkHasHref to LinkHasHrefCounter

---
 README.md                                     |  4 +-
 ...k-has-href.md => link-has-href-counter.md} |  8 ++-
 ...k_has_href.rb => link_has_href_counter.rb} | 21 +++++--
 .../link_has_href_counter_test.rb             | 59 +++++++++++++++++++
 .../accessibility/link_has_href_test.rb       | 23 --------
 5 files changed, 83 insertions(+), 32 deletions(-)
 rename docs/rules/accessibility/{link-has-href.md => link-has-href-counter.md} (54%)
 rename lib/erblint-github/linters/github/accessibility/{link_has_href.rb => link_has_href_counter.rb} (51%)
 create mode 100644 test/linters/accessibility/link_has_href_counter_test.rb
 delete mode 100644 test/linters/accessibility/link_has_href_test.rb

diff --git a/README.md b/README.md
index 2febb2a..a83b2f7 100644
--- a/README.md
+++ b/README.md
@@ -31,7 +31,7 @@ linters:
     enabled: true
   GitHub::Accessibility::ImageHasAlt:
     enabled: true
-  GitHub::Accessibility::LinkHasHref:
+  GitHub::Accessibility::LinkHasHrefCounter:
     enabled: true
   GitHub::Accessibility::NoAriaLabelMisuseCounter:
     enabled: true
@@ -49,7 +49,7 @@ linters:
 - [GitHub::Accessibility::AvoidGenericLinkTextCounter](./docs/rules/accessibility/avoid-generic-link-text-counter.md)
 - [GitHub::Accessibility::IframeHasTitle](./docs/rules/accessibility/iframe-has-title.md)
 - [GitHub::Accessibility::ImageHasAlt](./docs/rules/accessibility/image-has-alt.md)
-- [GitHub::Accessibility::LinkHasHref](./docs/rules/accessibility/link_has_href.md)
+- [GitHub::Accessibility::LinkHasHrefCounter](./docs/rules/accessibility/link_has_href-counter.md)
 - [GitHub::Accessibility::NoAriaLabelMisuseCounter](./docs/rules/accessibility/no-aria-label-misuse-counter.md)
 - [GitHub::Accessibility::NoPositiveTabIndex](./docs/rules/accessibility/no-positive-tab-index.md)
 - [GitHub::Accessibility::NoRedundantImageAlt](./docs/rules/accessibility/no-redundant-image-alt.md)
diff --git a/docs/rules/accessibility/link-has-href.md b/docs/rules/accessibility/link-has-href-counter.md
similarity index 54%
rename from docs/rules/accessibility/link-has-href.md
rename to docs/rules/accessibility/link-has-href-counter.md
index e172bc5..e902dd9 100644
--- a/docs/rules/accessibility/link-has-href.md
+++ b/docs/rules/accessibility/link-has-href-counter.md
@@ -1,13 +1,15 @@
-# Link Has Href
+# Link Has Href counter
 
 ## Rule Details
 
-Links should go somewhere, you probably want to use a `<button>` instead.
+An `<a>` element that has an href attribute represents a hyperlink (a hypertext anchor) labeled by its contents. Links, `<a>` elements, should go somewhere, you probably want to use a `<button>` instead.
+
 
 ## Resources
 
 - [`<a>`: The Anchor element](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a)
 - [Primer: Links](https://primer.style/design/accessibility/links)
+- [HTML Spec: The a element](https://html.spec.whatwg.org/multipage/text-level-semantics.html#the-a-element)
 
 ## Examples
 ### **Incorrect** code for this rule 👎
@@ -22,4 +24,4 @@ Links should go somewhere, you probably want to use a `<button>` instead.
 ```erb
 <!-- correct -->
 <a href='https://github.com/'>Go to GitHub</a>
-```
\ No newline at end of file
+```
diff --git a/lib/erblint-github/linters/github/accessibility/link_has_href.rb b/lib/erblint-github/linters/github/accessibility/link_has_href_counter.rb
similarity index 51%
rename from lib/erblint-github/linters/github/accessibility/link_has_href.rb
rename to lib/erblint-github/linters/github/accessibility/link_has_href_counter.rb
index dc21fbb..47d1698 100644
--- a/lib/erblint-github/linters/github/accessibility/link_has_href.rb
+++ b/lib/erblint-github/linters/github/accessibility/link_has_href_counter.rb
@@ -6,11 +6,11 @@ module ERBLint
   module Linters
     module GitHub
       module Accessibility
-        class LinkHasHref < Linter
+        class LinkHasHrefCounter < Linter
           include ERBLint::Linters::CustomHelpers
           include LinterRegistry
 
-          MESSAGE = "Links should go somewhere, you probably want to use a <button> instead."
+          MESSAGE = "Links should go somewhere, you probably want to use a `<button>` instead."
 
           def run(processed_source)
             tags(processed_source).each do |tag|
@@ -19,11 +19,24 @@ def run(processed_source)
 
               href = possible_attribute_values(tag, "href")
               name = tag.attributes["name"]
-
               generate_offense(self.class, processed_source, tag) if (!name && href.empty?) || href.include?("#")
             end
 
-            rule_disabled?(processed_source)
+            counter_correct?(processed_source)
+          end
+
+          def autocorrect(processed_source, offense)
+            return unless offense.context
+
+            lambda do |corrector|
+              if processed_source.file_content.include?("erblint:counter #{simple_class_name}")
+                # update the counter if exists
+                corrector.replace(offense.source_range, offense.context)
+              else
+                # add comment with counter if none
+                corrector.insert_before(processed_source.source_buffer.source_range, "#{offense.context}\n")
+              end
+            end
           end
         end
       end
diff --git a/test/linters/accessibility/link_has_href_counter_test.rb b/test/linters/accessibility/link_has_href_counter_test.rb
new file mode 100644
index 0000000..db6066d
--- /dev/null
+++ b/test/linters/accessibility/link_has_href_counter_test.rb
@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class LinkHasHrefCounter < LinterTestCase
+  def linter_class
+    ERBLint::Linters::GitHub::Accessibility::LinkHasHrefCounter
+  end
+
+  def test_warns_if_link_has_no_href_attribute
+    @file = "<a>Go to GitHub</a>"
+    @linter.run(processed_source)
+
+    assert_equal(2, @linter.offenses.count)
+    error_messages = @linter.offenses.map(&:message).sort
+    assert_match(/If you must, add <%# erblint:counter GitHub::Accessibility::LinkHasHrefCounter 1 %> to bypass this check./, error_messages.first)
+    assert_match(/Links should go somewhere, you probably want to use a `<button>` instead./, error_messages.last)
+  end
+
+  def test_does_not_warn_if_link_has_href_attribute
+    @file = "<a href='https://github.com/'>Go to GitHub</a>"
+    @linter.run(processed_source)
+
+    assert_empty @linter.offenses
+  end
+
+  def test_does_not_warn_if_link_has_href_attribute_and_has_correct_counter_comment
+    @file = <<~ERB
+      <%# erblint:counter GitHub::Accessibility::LinkHasHrefCounter 1 %>
+      <a>Go to GitHub</a>
+    ERB
+    @linter.run(processed_source)
+
+    assert_equal 0, @linter.offenses.count
+  end
+
+  def test_does_not_autocorrect_when_ignores_are_correct
+    @file = <<~ERB
+      <%# erblint:counter GitHub::Accessibility::LinkHasHrefCounter 1 %>
+      <a>Go to GitHub</a>
+    ERB
+
+    assert_equal @file, corrected_content
+  end
+
+  def test_does_autocorrect_when_ignores_are_not_correct
+    @file = <<~ERB
+      <%# erblint:counter GitHub::Accessibility::LinkHasHrefCounter 3 %>
+      <a>Go to GitHub</a>
+    ERB
+    refute_equal @file, corrected_content
+
+    expected_content = <<~ERB
+      <%# erblint:counter GitHub::Accessibility::LinkHasHrefCounter 1 %>
+      <a>Go to GitHub</a>
+    ERB
+    assert_equal expected_content, corrected_content
+  end
+end
diff --git a/test/linters/accessibility/link_has_href_test.rb b/test/linters/accessibility/link_has_href_test.rb
deleted file mode 100644
index 6251db1..0000000
--- a/test/linters/accessibility/link_has_href_test.rb
+++ /dev/null
@@ -1,23 +0,0 @@
-# frozen_string_literal: true
-
-require "test_helper"
-
-class LinkHasHref < LinterTestCase
-  def linter_class
-    ERBLint::Linters::GitHub::Accessibility::LinkHasHref
-  end
-
-  def test_warns_if_link_has_no_href_attribute
-    @file = "<a>Go to GitHub</a>"
-    @linter.run(processed_source)
-
-    refute_empty @linter.offenses
-  end
-
-  def test_does_not_warn_if_link_has_href_attribute
-    @file = "<a href='https://github.com/'>Go to GitHub</a>"
-    @linter.run(processed_source)
-
-    assert_empty @linter.offenses
-  end
-end