feat: bru lang - allow parsing empty header values

packages/bruno-lang/v2/src/index.js

@@ -12,7 +12,7 @@ const grammar = ohm.grammar(`Bru {
   headers = "headers" st* "{" pairlist? tagend
 
   pairlist = nl* pair (~tagend nl pair)* (~tagend space)*
-  pair = st* key st* ":" st* value st*
+  pair = st* key st* ":" st* value? st*
   key = ~tagend validkey*
   value = ~tagend validvalue*
 
@@ -58,7 +58,7 @@ const sem = grammar.createSemantics().addAttribute('ast', {
   },
   pair(_1, key, _2, _3, _4, value, _5) {
     let res = {};
-    res[key.ast] = value.ast;
+    res[key.ast] = _.get(value, 'ast[0]', '');
     return res;
   },
   key(chars) {

packages/bruno-lang/v2/tests/headers.spec.js

@@ -56,6 +56,23 @@ headers {
     assertSingleHeader(input);
   });
 
+  it("should parse single header with empty value", () => {
+    const input = `
+headers {
+  hello:
+}`;
+
+    const output = bruToJsonV2(input);
+    const expected = {
+      "headers": [{
+        "name": "hello",
+        "value": "",
+        "enabled": true
+      }]
+    };
+    expect(output).toEqual(expected);
+  });
+
   it("should parse multi headers", () => {
     const input = `
 headers {