fix: ignore else expressions and superfluous blocks

jg-rp · Feb 10, 2024 · e148c41 · e148c41
1 parent e3fdeae
commit e148c41
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Showing 3 changed files with 119 additions and 16 deletions.
diff --git a/src/builtin/tags/if.ts b/src/builtin/tags/if.ts
@@ -32,7 +32,7 @@ export class IfTag implements Tag {
     TOKEN_EOF,
   ]);
   protected static END_ELSEIF_BLOCK = new Set([TAG_ENDIF, TAG_ELSIF, TAG_ELSE]);
-  protected static END_ELSE_BLOCK = new Set([TAG_ENDIF]);
+  protected static END_ELSE_BLOCK = new Set([TAG_ENDIF, TAG_ELSIF, TAG_ELSE]);
 
   readonly block = true;
   readonly name: string = TAG_IF;
@@ -71,24 +71,45 @@ export class IfTag implements Tag {
       });
     }
 
+    let alternative: BlockNode | undefined = undefined;
+
     if (
       stream.current.kind === TOKEN_TAG &&
       stream.current.value === TAG_ELSE
     ) {
-      return new this.nodeClass(
-        token,
-        condition,
-        consequence,
-        conditionalAlternatives,
-        parser.parseBlock(stream, IfTag.END_ELSE_BLOCK, stream.next()),
-      );
+      const tok = stream.next();
+      // @ts-expect-error: stream.current has changed, so `kind` will have changed too.
+      if (stream.current.kind === TOKEN_EXPRESSION) {
+        // Superfluous expressions inside an `else` tag are ignored.
+        stream.next();
+      }
+
+      alternative = parser.parseBlock(stream, IfTag.END_ELSE_BLOCK, tok);
     }
 
+    // Extraneous `else` and `elsif` blocks are ignored.
+    if (
+      !(stream.current.kind === TOKEN_TAG && stream.current.value === TAG_ENDIF)
+    ) {
+      while (stream.current.kind !== TOKEN_EOF) {
+        if (
+          stream.current.kind === TOKEN_TAG &&
+          stream.current.value === TAG_ENDIF
+        ) {
+          break;
+        }
+        stream.next();
+      }
+    }
+
+    stream.expectTag(TAG_ENDIF);
+
     return new this.nodeClass(
       token,
       condition,
       consequence,
       conditionalAlternatives,
+      alternative,
     );
   }
 }

diff --git a/src/builtin/tags/unless.ts b/src/builtin/tags/unless.ts
@@ -31,12 +31,18 @@ export class UnlessTag implements Tag {
     TAG_ELSE,
     TOKEN_EOF,
   ]);
+
   protected static END_ELSEIF_BLOCK = new Set([
     TAG_ENDUNLESS,
     TAG_ELSIF,
     TAG_ELSE,
   ]);
-  protected static END_ELSE_BLOCK = new Set([TAG_ENDUNLESS]);
+
+  protected static END_ELSE_BLOCK = new Set([
+    TAG_ENDUNLESS,
+    TAG_ELSIF,
+    TAG_ELSE,
+  ]);
 
   readonly block = true;
   readonly name: string = TAG_UNLESS;
@@ -79,24 +85,46 @@ export class UnlessTag implements Tag {
       });
     }
 
+    let alternative: BlockNode | undefined = undefined;
+
     if (
       stream.current.kind === TOKEN_TAG &&
       stream.current.value === TAG_ELSE
     ) {
-      return new this.nodeClass(
-        token,
-        condition,
-        consequence,
-        conditionalAlternatives,
-        parser.parseBlock(stream, UnlessTag.END_ELSE_BLOCK, stream.next()),
-      );
+      const tok = stream.next();
+      // @ts-expect-error: stream.current has changed, so `kind` will have changed too.
+      if (stream.current.kind === TOKEN_EXPRESSION) {
+        // Superfluous expressions inside an `else` tag are ignored.
+        stream.next();
+      }
+
+      alternative = parser.parseBlock(stream, UnlessTag.END_ELSE_BLOCK, tok);
+    }
+
+    // Extraneous `else` and `elsif` blocks are ignored.
+    if (
+      !(
+        stream.current.kind === TOKEN_TAG &&
+        stream.current.value === TAG_ENDUNLESS
+      )
+    ) {
+      while (stream.current.kind !== TOKEN_EOF) {
+        if (
+          stream.current.kind === TOKEN_TAG &&
+          stream.current.value === TAG_ENDUNLESS
+        ) {
+          break;
+        }
+        stream.next();
+      }
     }
 
     return new this.nodeClass(
       token,
       condition,
       consequence,
       conditionalAlternatives,
+      alternative,
     );
   }
 }

diff --git a/tests/golden/golden_liquid.json b/tests/golden/golden_liquid.json
@@ -3865,6 +3865,33 @@
                     "error": false,
                     "strict": false
                 },
+                {
+                    "name": "else tag expressions are ignored",
+                    "template": "{% if false %}1{% else nonsense %}2{% endif %}",
+                    "want": "2",
+                    "context": {},
+                    "partials": {},
+                    "error": false,
+                    "strict": true
+                },
+                {
+                    "name": "extra else blocks are ignored",
+                    "template": "{% if false %}1{% else %}2{% else %}3{% endif %}",
+                    "want": "2",
+                    "context": {},
+                    "partials": {},
+                    "error": false,
+                    "strict": true
+                },
+                {
+                    "name": "extra elsif blocks are ignored",
+                    "template": "{% if false %}1{% else %}2{% elsif true %}3{% endif %}",
+                    "want": "2",
+                    "context": {},
+                    "partials": {},
+                    "error": false,
+                    "strict": true
+                },
                 {
                     "name": "int does not equal string",
                     "template": "{% if 1 == '1' %}true{% else %}false{% endif %}",
@@ -9335,6 +9362,33 @@
                     "error": false,
                     "strict": false
                 },
+                {
+                    "name": "else tag expressions are ignored",
+                    "template": "{% unless true %}1{% else nonsense %}2{% endunless %}",
+                    "want": "2",
+                    "context": {},
+                    "partials": {},
+                    "error": false,
+                    "strict": true
+                },
+                {
+                    "name": "extra else blocks are ignored",
+                    "template": "{% unless true %}1{% else %}2{% else %}3{% endunless %}",
+                    "want": "2",
+                    "context": {},
+                    "partials": {},
+                    "error": false,
+                    "strict": true
+                },
+                {
+                    "name": "extra elsif blocks are ignored",
+                    "template": "{% unless true %}1{% else %}2{% elsif true %}3{% endunless %}",
+                    "want": "2",
+                    "context": {},
+                    "partials": {},
+                    "error": false,
+                    "strict": true
+                },
                 {
                     "name": "literal false condition",
                     "template": "{% unless false %}foo{% endunless %}",