diff --git a/core/badge-urls/path-helpers.js b/core/badge-urls/path-helpers.js
index 81c7222fe4..b7b3bded44 100644
--- a/core/badge-urls/path-helpers.js
+++ b/core/badge-urls/path-helpers.js
@@ -5,11 +5,8 @@
 function escapeFormat(t) {
   return (
     t
-      // Inline single underscore.
-      .replace(/([^_])_([^_])/g, '$1 $2')
-      // Leading or trailing underscore.
-      .replace(/([^_])_$/, '$1 ')
-      .replace(/^_([^_])/, ' $1')
+      // Single underscore.
+      .replace(/(^|[^_])((?:__)*)_(?!_)/g, '$1$2 ')
       // Double underscore and double dash.
       .replace(/__/g, '_')
       .replace(/--/g, '-')
diff --git a/core/badge-urls/path-helpers.spec.js b/core/badge-urls/path-helpers.spec.js
new file mode 100644
index 0000000000..ef7a0068e1
--- /dev/null
+++ b/core/badge-urls/path-helpers.spec.js
@@ -0,0 +1,21 @@
+'use strict'
+
+const { test, given } = require('sazerac')
+const { escapeFormat } = require('./path-helpers')
+
+describe('Badge URL helper functions', function () {
+  test(escapeFormat, () => {
+    given('_single leading underscore').expect(' single leading underscore')
+    given('single trailing underscore_').expect('single trailing underscore ')
+    given('__double leading underscores').expect('_double leading underscores')
+    given('double trailing underscores__').expect(
+      'double trailing underscores_'
+    )
+    given('treble___underscores').expect('treble_ underscores')
+    given('fourfold____underscores').expect('fourfold__underscores')
+    given('double--dashes').expect('double-dashes')
+    given('treble---dashes').expect('treble--dashes')
+    given('fourfold----dashes').expect('fourfold--dashes')
+    given('once_in_a_blue--moon').expect('once in a blue-moon')
+  })
+})