diff --git a/src/parser/statement.js b/src/parser/statement.js
index 5c9d27145e..6b534ba232 100644
--- a/src/parser/statement.js
+++ b/src/parser/statement.js
@@ -60,6 +60,11 @@ pp.parseStatement = function (declaration, topLevel) {
 
   const starttype = this.state.type;
   const node = this.startNode();
+  let expr = null;
+  let objParseError = null;
+
+  const isBlock = this.state.nextBraceIsBlock;
+  if (this.state.nextBraceIsBlock !== undefined) delete this.state.nextBraceIsBlock;
 
   // Most types of statements are recognized by the keyword they
   // start with. Many are trivial to parse, some require a bit of
@@ -94,10 +99,32 @@ pp.parseStatement = function (declaration, topLevel) {
     case tt._while: return this.parseWhileStatement(node);
     case tt._with: return this.parseWithStatement(node);
     case tt.braceL:
-      // in lightscript, allow line-starting `{` to be parsed as obj or obj pattern
-      if (this.hasPlugin("lightscript") && this.isLineBreak()) {
+      if (this.hasPlugin("whiteblockOnly")) {
+        // whiteblockOnly = what follows must be an ObjectExpression/Pattern
         break;
-      } else if (this.hasPlugin("whiteblockOnly")) {
+      } else if (this.hasPlugin("whiteblockPreferred") && !isBlock) {
+        // whiteblockPreferred = try to parse as obj, otherwise rewind and parse as block
+        const state = this.state.clone();
+        try {
+          expr = this.parseExpression();
+          break;
+        } catch (err) {
+          this.state = state;
+          objParseError = err;
+        }
+
+        try {
+          return this.parseBlock();
+        } catch (err) {
+          if (objParseError && objParseError.pos >= err.pos) {
+            throw objParseError;
+          } else {
+            throw err;
+          }
+        }
+      } else if (this.hasPlugin("lightscript") && this.isLineBreak() && !isBlock) {
+        // legacy lsc behavior
+        // allow line-starting `{` to be parsed as obj or obj pattern
         break;
       } else {
         return this.parseBlock();
@@ -141,7 +168,7 @@ pp.parseStatement = function (declaration, topLevel) {
   // next token is a colon and the expression was a simple
   // Identifier node, we switch to interpreting it as a label.
   const maybeName = this.state.value;
-  const expr = this.parseExpression();
+  if (!expr) expr = this.parseExpression();
 
   // rewrite `x = val` and `x: type = val`
   if (this.hasPlugin("lightscript") && this.isColonConstAssign(expr)) {
@@ -238,6 +265,8 @@ pp.parseDoStatement = function (node) {
     isWhiteBlock = true;
     indentLevel = this.state.indentLevel;
   }
+
+  this.state.nextBraceIsBlock = true;
   node.body = this.parseStatement(false);
   this.state.labels.pop();
   if (this.hasPlugin("lightscript") && isWhiteBlock && this.state.indentLevel !== indentLevel) {
@@ -530,6 +559,7 @@ pp.parseWhileStatement = function (node) {
   this.next();
   node.test = this.parseParenExpression();
   this.state.labels.push(loopLabel);
+  this.state.nextBraceIsBlock = true;
   node.body = this.parseStatement(false);
   this.state.labels.pop();
   return this.finishNode(node, "WhileStatement");
@@ -673,6 +703,7 @@ pp.parseFor = function (node, init) {
     this.expect(tt.parenR);
   }
 
+  this.state.nextBraceIsBlock = true;
   node.body = this.parseStatement(false);
   this.state.labels.pop();
   return this.finishNode(node, "ForStatement");
@@ -699,6 +730,7 @@ pp.parseForIn = function (node, init, forAwait) {
     this.expect(tt.parenR);
   }
 
+  this.state.nextBraceIsBlock = true;
   node.body = this.parseStatement(false);
   this.state.labels.pop();
   return this.finishNode(node, type);
diff --git a/src/plugins/lightscript.js b/src/plugins/lightscript.js
index 9a61cea3b8..aae45f8d83 100644
--- a/src/plugins/lightscript.js
+++ b/src/plugins/lightscript.js
@@ -96,6 +96,7 @@ pp.parseEnhancedForIn = function (node) {
   const iterable = this.parseMaybeAssign(true);
 
   this.expectParenFreeBlockStart(node);
+  this.state.nextBraceIsBlock = true;
   node.body = this.parseStatement(false);
 
   if ((matchingIterationType === "idx") || (matchingIterationType === "elem")) {
@@ -460,6 +461,7 @@ pp.parseIf = function (node, isExpression, requireColon = null) {
     this.state.inFunction = oldInFunction;
     this.state.labels = oldLabels;
   } else {
+    this.state.nextBraceIsBlock = true;
     node.consequent = this.parseStatement(false);
   }
 
@@ -510,6 +512,7 @@ pp.parseIfAlternate = function (node, isExpression, ifIsWhiteBlock, ifIndentLeve
       }
     }
 
+    this.state.nextBraceIsBlock = true;
     return this.parseStatement(false);
   }
 
@@ -689,6 +692,7 @@ export default function (instance) {
   instance.extend("parseStatement", function (inner) {
     return function () {
       if (this.match(tt.colon)) {
+        delete this.state.nextBraceIsBlock;
         return this.parseWhiteBlock();
       }
       return inner.apply(this, arguments);
diff --git a/test/fixtures/core/categorized/label-kind-switch/options.lightscript.json b/test/fixtures/core/categorized/label-kind-switch/options.lightscript.json
deleted file mode 100644
index 43de8d051d..0000000000
--- a/test/fixtures/core/categorized/label-kind-switch/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (2:5)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/214/options.lightscript.json b/test/fixtures/core/uncategorised/214/options.lightscript.json
deleted file mode 100644
index 779ebfe878..0000000000
--- a/test/fixtures/core/uncategorised/214/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected { (1:10)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/235/options.lightscript.json b/test/fixtures/core/uncategorised/235/options.lightscript.json
deleted file mode 100644
index 78b21c5363..0000000000
--- a/test/fixtures/core/uncategorised/235/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:5)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/300/options.lightscript.json b/test/fixtures/core/uncategorised/300/options.lightscript.json
deleted file mode 100644
index 0361d7c7d2..0000000000
--- a/test/fixtures/core/uncategorised/300/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (2:0)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/301/options.lightscript.json b/test/fixtures/core/uncategorised/301/options.lightscript.json
deleted file mode 100644
index 0361d7c7d2..0000000000
--- a/test/fixtures/core/uncategorised/301/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (2:0)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/303/options.lightscript.json b/test/fixtures/core/uncategorised/303/options.lightscript.json
deleted file mode 100644
index 5a91ab8f84..0000000000
--- a/test/fixtures/core/uncategorised/303/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:6)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/313/options.lightscript.json b/test/fixtures/core/uncategorised/313/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/core/uncategorised/313/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/314/options.lightscript.json b/test/fixtures/core/uncategorised/314/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/core/uncategorised/314/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/315/options.lightscript.json b/test/fixtures/core/uncategorised/315/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/core/uncategorised/315/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/332/options.lightscript.json b/test/fixtures/core/uncategorised/332/options.lightscript.json
deleted file mode 100644
index 04b967a2ee..0000000000
--- a/test/fixtures/core/uncategorised/332/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (1:1)"
-}
\ No newline at end of file
diff --git a/test/fixtures/core/uncategorised/336/options.lightscript.json b/test/fixtures/core/uncategorised/336/options.lightscript.json
deleted file mode 100644
index 9f7910a413..0000000000
--- a/test/fixtures/core/uncategorised/336/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (1:4)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0000/options.lightscript.json b/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0000/options.lightscript.json
deleted file mode 100644
index 0361d7c7d2..0000000000
--- a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0000/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (2:0)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0001/options.lightscript.json b/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0001/options.lightscript.json
deleted file mode 100644
index 0361d7c7d2..0000000000
--- a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0001/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (2:0)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0003/options.lightscript.json b/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0003/options.lightscript.json
deleted file mode 100644
index 5a91ab8f84..0000000000
--- a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0003/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:6)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0013/options.lightscript.json b/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0013/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0013/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0014/options.lightscript.json b/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0014/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0014/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0015/options.lightscript.json b/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0015/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/esprima/automatic-semicolon-insertion/migrated_0015/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/declaration-const/migrated_0001/options.lightscript.json b/test/fixtures/esprima/declaration-const/migrated_0001/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/esprima/declaration-const/migrated_0001/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/declaration-const/migrated_0002/options.lightscript.json b/test/fixtures/esprima/declaration-const/migrated_0002/options.lightscript.json
deleted file mode 100644
index 930a14478b..0000000000
--- a/test/fixtures/esprima/declaration-const/migrated_0002/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:8)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/declaration-let/migrated_0001/options.lightscript.json b/test/fixtures/esprima/declaration-let/migrated_0001/options.lightscript.json
deleted file mode 100644
index 5a91ab8f84..0000000000
--- a/test/fixtures/esprima/declaration-let/migrated_0001/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:6)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/declaration-let/migrated_0002/options.lightscript.json b/test/fixtures/esprima/declaration-let/migrated_0002/options.lightscript.json
deleted file mode 100644
index 5a91ab8f84..0000000000
--- a/test/fixtures/esprima/declaration-let/migrated_0002/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:6)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/declaration-let/migrated_0003/options.lightscript.json b/test/fixtures/esprima/declaration-let/migrated_0003/options.lightscript.json
deleted file mode 100644
index 5a91ab8f84..0000000000
--- a/test/fixtures/esprima/declaration-let/migrated_0003/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected , (1:6)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/invalid-syntax/migrated_0255/options.lightscript.json b/test/fixtures/esprima/invalid-syntax/migrated_0255/options.lightscript.json
deleted file mode 100644
index e68fbb6aec..0000000000
--- a/test/fixtures/esprima/invalid-syntax/migrated_0255/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (1:2)"
-}
\ No newline at end of file
diff --git a/test/fixtures/esprima/statement-block/migrated_0001/options.lightscript.json b/test/fixtures/esprima/statement-block/migrated_0001/options.lightscript.json
deleted file mode 100644
index 678798b61e..0000000000
--- a/test/fixtures/esprima/statement-block/migrated_0001/options.lightscript.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token, expected { (1:10)"
-}
diff --git a/test/fixtures/esprima/statement-iteration/migrated_0003/options.lightscript.json b/test/fixtures/esprima/statement-iteration/migrated_0003/options.lightscript.json
index 2d4f18af3e..bdd84a6c76 100644
--- a/test/fixtures/esprima/statement-iteration/migrated_0003/options.lightscript.json
+++ b/test/fixtures/esprima/statement-iteration/migrated_0003/options.lightscript.json
@@ -1,3 +1,3 @@
 {
-  "throws": "Unexpected token, expected , (1:5)"
+  "throws": "Unexpected token, expected ; (1:23)"
 }
diff --git a/test/fixtures/lightscript/auto-const/not-newline-object-malformed-unfortunate/expected.json b/test/fixtures/lightscript/auto-const/not-newline-object-malformed-unfortunate/expected.json
new file mode 100644
index 0000000000..e060b1e68f
--- /dev/null
+++ b/test/fixtures/lightscript/auto-const/not-newline-object-malformed-unfortunate/expected.json
@@ -0,0 +1,245 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 14,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 14
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 14,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 14
+      }
+    },
+    "sourceType": "script",
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start": 0,
+        "end": 2,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 2
+          }
+        },
+        "expression": {
+          "type": "Identifier",
+          "start": 0,
+          "end": 1,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 1
+            },
+            "identifierName": "x"
+          },
+          "name": "x"
+        }
+      },
+      {
+        "type": "VariableDeclaration",
+        "start": 3,
+        "end": 14,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 3
+          },
+          "end": {
+            "line": 1,
+            "column": 14
+          }
+        },
+        "kind": "const",
+        "extra": {
+          "implicit": true
+        },
+        "declarations": [
+          {
+            "type": "VariableDeclarator",
+            "start": 3,
+            "end": 14,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 3
+              },
+              "end": {
+                "line": 1,
+                "column": 14
+              }
+            },
+            "id": {
+              "type": "ObjectPattern",
+              "start": 3,
+              "end": 9,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 3
+                },
+                "end": {
+                  "line": 1,
+                  "column": 9
+                }
+              },
+              "properties": [
+                {
+                  "type": "ObjectProperty",
+                  "start": 4,
+                  "end": 5,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 4
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 5
+                    }
+                  },
+                  "method": false,
+                  "shorthand": true,
+                  "computed": false,
+                  "key": {
+                    "type": "Identifier",
+                    "start": 4,
+                    "end": 5,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 4
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 5
+                      },
+                      "identifierName": "a"
+                    },
+                    "name": "a"
+                  },
+                  "value": {
+                    "type": "Identifier",
+                    "start": 4,
+                    "end": 5,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 4
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 5
+                      },
+                      "identifierName": "a"
+                    },
+                    "name": "a"
+                  },
+                  "extra": {
+                    "shorthand": true
+                  }
+                },
+                {
+                  "type": "ObjectProperty",
+                  "start": 7,
+                  "end": 8,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 7
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 8
+                    }
+                  },
+                  "method": false,
+                  "shorthand": true,
+                  "computed": false,
+                  "key": {
+                    "type": "Identifier",
+                    "start": 7,
+                    "end": 8,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 7
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 8
+                      },
+                      "identifierName": "b"
+                    },
+                    "name": "b"
+                  },
+                  "value": {
+                    "type": "Identifier",
+                    "start": 7,
+                    "end": 8,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 7
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 8
+                      },
+                      "identifierName": "b"
+                    },
+                    "name": "b"
+                  },
+                  "extra": {
+                    "shorthand": true
+                  }
+                }
+              ]
+            },
+            "init": {
+              "type": "ObjectExpression",
+              "start": 12,
+              "end": 14,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 12
+                },
+                "end": {
+                  "line": 1,
+                  "column": 14
+                }
+              },
+              "properties": []
+            }
+          }
+        ]
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/lightscript/auto-const/not-newline-object-malformed-unfortunate/options.json b/test/fixtures/lightscript/auto-const/not-newline-object-malformed-unfortunate/options.json
index ec40224464..ddde482277 100644
--- a/test/fixtures/lightscript/auto-const/not-newline-object-malformed-unfortunate/options.json
+++ b/test/fixtures/lightscript/auto-const/not-newline-object-malformed-unfortunate/options.json
@@ -1,8 +1,5 @@
 {
   "alternatives": {
-    "all": {
-      "throws": "Unexpected token (1:5)"
-    },
     "noSeqExprParens": {
       "allPlugins": true,
       "excludePlugins": ["existentialExpression", "safeCallExpression", "splatComprehension", "seqExprRequiresParen", "bangCall", "whiteblockOnly", "whiteblockPreferred"],
diff --git a/test/fixtures/lightscript/blocks/anonymous-blocks-no-semi/actual.js b/test/fixtures/lightscript/blocks/anonymous-blocks-no-semi/actual.js
new file mode 100644
index 0000000000..ed5e62d6fe
--- /dev/null
+++ b/test/fixtures/lightscript/blocks/anonymous-blocks-no-semi/actual.js
@@ -0,0 +1,6 @@
+fn() ->
+  a = 1
+  {
+    a = 2
+  }
+  a
diff --git a/test/fixtures/lightscript/blocks/anonymous-blocks-no-semi/expected.json b/test/fixtures/lightscript/blocks/anonymous-blocks-no-semi/expected.json
new file mode 100644
index 0000000000..3edda41ae2
--- /dev/null
+++ b/test/fixtures/lightscript/blocks/anonymous-blocks-no-semi/expected.json
@@ -0,0 +1,291 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 37,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 6,
+      "column": 3
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 37,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 6,
+        "column": 3
+      }
+    },
+    "sourceType": "script",
+    "body": [
+      {
+        "type": "NamedArrowDeclaration",
+        "start": 0,
+        "end": 37,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 6,
+            "column": 3
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 0,
+          "end": 2,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 2
+            },
+            "identifierName": "fn"
+          },
+          "name": "fn"
+        },
+        "generator": false,
+        "expression": false,
+        "async": false,
+        "params": [],
+        "skinny": true,
+        "body": {
+          "type": "BlockStatement",
+          "start": 5,
+          "end": 37,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 5
+            },
+            "end": {
+              "line": 6,
+              "column": 3
+            }
+          },
+          "body": [
+            {
+              "type": "VariableDeclaration",
+              "start": 10,
+              "end": 15,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 2
+                },
+                "end": {
+                  "line": 2,
+                  "column": 7
+                }
+              },
+              "kind": "const",
+              "extra": {
+                "implicit": true
+              },
+              "declarations": [
+                {
+                  "type": "VariableDeclarator",
+                  "start": 10,
+                  "end": 15,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 2
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 7
+                    }
+                  },
+                  "id": {
+                    "type": "Identifier",
+                    "start": 10,
+                    "end": 11,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 2
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 3
+                      },
+                      "identifierName": "a"
+                    },
+                    "name": "a"
+                  },
+                  "init": {
+                    "type": "NumericLiteral",
+                    "start": 14,
+                    "end": 15,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 6
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 7
+                      }
+                    },
+                    "extra": {
+                      "rawValue": 1,
+                      "raw": "1"
+                    },
+                    "value": 1
+                  }
+                }
+              ]
+            },
+            {
+              "type": "BlockStatement",
+              "start": 18,
+              "end": 33,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 2
+                },
+                "end": {
+                  "line": 5,
+                  "column": 3
+                }
+              },
+              "body": [
+                {
+                  "type": "VariableDeclaration",
+                  "start": 24,
+                  "end": 29,
+                  "loc": {
+                    "start": {
+                      "line": 4,
+                      "column": 4
+                    },
+                    "end": {
+                      "line": 4,
+                      "column": 9
+                    }
+                  },
+                  "kind": "const",
+                  "extra": {
+                    "implicit": true
+                  },
+                  "declarations": [
+                    {
+                      "type": "VariableDeclarator",
+                      "start": 24,
+                      "end": 29,
+                      "loc": {
+                        "start": {
+                          "line": 4,
+                          "column": 4
+                        },
+                        "end": {
+                          "line": 4,
+                          "column": 9
+                        }
+                      },
+                      "id": {
+                        "type": "Identifier",
+                        "start": 24,
+                        "end": 25,
+                        "loc": {
+                          "start": {
+                            "line": 4,
+                            "column": 4
+                          },
+                          "end": {
+                            "line": 4,
+                            "column": 5
+                          },
+                          "identifierName": "a"
+                        },
+                        "name": "a"
+                      },
+                      "init": {
+                        "type": "NumericLiteral",
+                        "start": 28,
+                        "end": 29,
+                        "loc": {
+                          "start": {
+                            "line": 4,
+                            "column": 8
+                          },
+                          "end": {
+                            "line": 4,
+                            "column": 9
+                          }
+                        },
+                        "extra": {
+                          "rawValue": 2,
+                          "raw": "2"
+                        },
+                        "value": 2
+                      }
+                    }
+                  ]
+                }
+              ],
+              "directives": [],
+              "extra": {
+                "curly": true
+              }
+            },
+            {
+              "type": "ExpressionStatement",
+              "start": 36,
+              "end": 37,
+              "loc": {
+                "start": {
+                  "line": 6,
+                  "column": 2
+                },
+                "end": {
+                  "line": 6,
+                  "column": 3
+                }
+              },
+              "expression": {
+                "type": "Identifier",
+                "start": 36,
+                "end": 37,
+                "loc": {
+                  "start": {
+                    "line": 6,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 6,
+                    "column": 3
+                  },
+                  "identifierName": "a"
+                },
+                "name": "a"
+              }
+            }
+          ],
+          "directives": [],
+          "extra": {
+            "curly": false
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/lightscript/blocks/broken-curly-blocks/expected.json b/test/fixtures/lightscript/blocks/broken-curly-blocks/expected.json
new file mode 100644
index 0000000000..a843df051e
--- /dev/null
+++ b/test/fixtures/lightscript/blocks/broken-curly-blocks/expected.json
@@ -0,0 +1,159 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 21,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 4,
+      "column": 1
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 21,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 4,
+        "column": 1
+      }
+    },
+    "sourceType": "script",
+    "body": [
+      {
+        "type": "IfStatement",
+        "start": 0,
+        "end": 21,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 4,
+            "column": 1
+          }
+        },
+        "test": {
+          "type": "BooleanLiteral",
+          "start": 4,
+          "end": 8,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 4
+            },
+            "end": {
+              "line": 1,
+              "column": 8
+            }
+          },
+          "value": true,
+          "extra": {}
+        },
+        "consequent": {
+          "type": "BlockStatement",
+          "start": 10,
+          "end": 21,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 0
+            },
+            "end": {
+              "line": 4,
+              "column": 1
+            }
+          },
+          "body": [
+            {
+              "type": "ExpressionStatement",
+              "start": 14,
+              "end": 19,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 2
+                },
+                "end": {
+                  "line": 3,
+                  "column": 7
+                }
+              },
+              "expression": {
+                "type": "BinaryExpression",
+                "start": 14,
+                "end": 19,
+                "loc": {
+                  "start": {
+                    "line": 3,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 3,
+                    "column": 7
+                  }
+                },
+                "left": {
+                  "type": "NumericLiteral",
+                  "start": 14,
+                  "end": 15,
+                  "loc": {
+                    "start": {
+                      "line": 3,
+                      "column": 2
+                    },
+                    "end": {
+                      "line": 3,
+                      "column": 3
+                    }
+                  },
+                  "extra": {
+                    "rawValue": 1,
+                    "raw": "1"
+                  },
+                  "value": 1
+                },
+                "operator": "+",
+                "right": {
+                  "type": "NumericLiteral",
+                  "start": 18,
+                  "end": 19,
+                  "loc": {
+                    "start": {
+                      "line": 3,
+                      "column": 6
+                    },
+                    "end": {
+                      "line": 3,
+                      "column": 7
+                    }
+                  },
+                  "extra": {
+                    "rawValue": 1,
+                    "raw": "1"
+                  },
+                  "value": 1
+                }
+              }
+            }
+          ],
+          "directives": [],
+          "extra": {
+            "curly": true
+          }
+        },
+        "alternate": null
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/lightscript/blocks/broken-curly-blocks/options.json b/test/fixtures/lightscript/blocks/broken-curly-blocks/options.json
deleted file mode 100644
index 951efd6fb4..0000000000
--- a/test/fixtures/lightscript/blocks/broken-curly-blocks/options.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Unexpected token (3:4)"
-}
diff --git a/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/actual.js b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/actual.js
new file mode 100644
index 0000000000..09f6a16f5c
--- /dev/null
+++ b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/actual.js
@@ -0,0 +1 @@
+a; { b } = c
diff --git a/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/expected.json b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/expected.json
new file mode 100644
index 0000000000..b279456b0e
--- /dev/null
+++ b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/expected.json
@@ -0,0 +1,191 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 12,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 12
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 12,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 12
+      }
+    },
+    "sourceType": "script",
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start": 0,
+        "end": 2,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 2
+          }
+        },
+        "expression": {
+          "type": "Identifier",
+          "start": 0,
+          "end": 1,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 1
+            },
+            "identifierName": "a"
+          },
+          "name": "a"
+        }
+      },
+      {
+        "type": "VariableDeclaration",
+        "start": 3,
+        "end": 12,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 3
+          },
+          "end": {
+            "line": 1,
+            "column": 12
+          }
+        },
+        "kind": "const",
+        "extra": {
+          "implicit": true
+        },
+        "declarations": [
+          {
+            "type": "VariableDeclarator",
+            "start": 3,
+            "end": 12,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 3
+              },
+              "end": {
+                "line": 1,
+                "column": 12
+              }
+            },
+            "id": {
+              "type": "ObjectPattern",
+              "start": 3,
+              "end": 8,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 3
+                },
+                "end": {
+                  "line": 1,
+                  "column": 8
+                }
+              },
+              "properties": [
+                {
+                  "type": "ObjectProperty",
+                  "start": 5,
+                  "end": 6,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 5
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 6
+                    }
+                  },
+                  "method": false,
+                  "shorthand": true,
+                  "computed": false,
+                  "key": {
+                    "type": "Identifier",
+                    "start": 5,
+                    "end": 6,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 5
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 6
+                      },
+                      "identifierName": "b"
+                    },
+                    "name": "b"
+                  },
+                  "value": {
+                    "type": "Identifier",
+                    "start": 5,
+                    "end": 6,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 5
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 6
+                      },
+                      "identifierName": "b"
+                    },
+                    "name": "b"
+                  },
+                  "extra": {
+                    "shorthand": true
+                  }
+                }
+              ]
+            },
+            "init": {
+              "type": "Identifier",
+              "start": 11,
+              "end": 12,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 11
+                },
+                "end": {
+                  "line": 1,
+                  "column": 12
+                },
+                "identifierName": "c"
+              },
+              "name": "c"
+            }
+          }
+        ]
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/expected.whiteblockOnly.json b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/expected.whiteblockOnly.json
new file mode 100644
index 0000000000..b279456b0e
--- /dev/null
+++ b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/expected.whiteblockOnly.json
@@ -0,0 +1,191 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 12,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 12
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 12,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 12
+      }
+    },
+    "sourceType": "script",
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start": 0,
+        "end": 2,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 2
+          }
+        },
+        "expression": {
+          "type": "Identifier",
+          "start": 0,
+          "end": 1,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 1
+            },
+            "identifierName": "a"
+          },
+          "name": "a"
+        }
+      },
+      {
+        "type": "VariableDeclaration",
+        "start": 3,
+        "end": 12,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 3
+          },
+          "end": {
+            "line": 1,
+            "column": 12
+          }
+        },
+        "kind": "const",
+        "extra": {
+          "implicit": true
+        },
+        "declarations": [
+          {
+            "type": "VariableDeclarator",
+            "start": 3,
+            "end": 12,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 3
+              },
+              "end": {
+                "line": 1,
+                "column": 12
+              }
+            },
+            "id": {
+              "type": "ObjectPattern",
+              "start": 3,
+              "end": 8,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 3
+                },
+                "end": {
+                  "line": 1,
+                  "column": 8
+                }
+              },
+              "properties": [
+                {
+                  "type": "ObjectProperty",
+                  "start": 5,
+                  "end": 6,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 5
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 6
+                    }
+                  },
+                  "method": false,
+                  "shorthand": true,
+                  "computed": false,
+                  "key": {
+                    "type": "Identifier",
+                    "start": 5,
+                    "end": 6,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 5
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 6
+                      },
+                      "identifierName": "b"
+                    },
+                    "name": "b"
+                  },
+                  "value": {
+                    "type": "Identifier",
+                    "start": 5,
+                    "end": 6,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 5
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 6
+                      },
+                      "identifierName": "b"
+                    },
+                    "name": "b"
+                  },
+                  "extra": {
+                    "shorthand": true
+                  }
+                }
+              ]
+            },
+            "init": {
+              "type": "Identifier",
+              "start": 11,
+              "end": 12,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 11
+                },
+                "end": {
+                  "line": 1,
+                  "column": 12
+                },
+                "identifierName": "c"
+              },
+              "name": "c"
+            }
+          }
+        ]
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/options.json b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/options.json
new file mode 100644
index 0000000000..fdc47aacf1
--- /dev/null
+++ b/test/fixtures/lightscript/object-block-ambiguity/semi-assignment-pattern/options.json
@@ -0,0 +1,7 @@
+{
+  "alternatives": {
+    "braceblock": {
+      "throws": "Unexpected token (1:9)"
+    }
+  }
+}