Fixes (#294)

swc_ecma_transforms:
  - block_scoped_fn: don't fold self-modifing functions. (#288).
  - fixer: fix assignment in conditional expression (#293)
  - make resolver work with self modifying function (#292)

ecmascript/transforms/src/compat/es2015/block_scoped_fn.rs

@@ -1,3 +1,4 @@
+use crate::util::UsageFinder;
 use ast::*;
 use swc_common::{Fold, FoldWith, Spanned, DUMMY_SP};
 
@@ -15,20 +16,26 @@ impl Fold<Vec<Stmt>> for BlockScopedFns {
                 extra_stmts.push(stmt)
             } else {
                 match stmt {
-                    Stmt::Decl(Decl::Fn(decl)) => stmts.push(Stmt::Decl(Decl::Var(VarDecl {
-                        span: DUMMY_SP,
-                        kind: VarDeclKind::Let,
-                        decls: vec![VarDeclarator {
+                    Stmt::Decl(Decl::Fn(decl)) => {
+                        if UsageFinder::find(&decl.ident, &decl.function) {
+                            extra_stmts.push(Stmt::Decl(Decl::Fn(decl)));
+                            continue;
+                        }
+                        stmts.push(Stmt::Decl(Decl::Var(VarDecl {
                             span: DUMMY_SP,
-                            name: Pat::Ident(decl.ident.clone()),
-                            init: Some(box Expr::Fn(FnExpr {
-                                ident: Some(decl.ident),
-                                function: decl.function,
-                            })),
-                            definite: false,
-                        }],
-                        declare: false,
-                    }))),
+                            kind: VarDeclKind::Let,
+                            decls: vec![VarDeclarator {
+                                span: DUMMY_SP,
+                                name: Pat::Ident(decl.ident.clone()),
+                                init: Some(box Expr::Fn(FnExpr {
+                                    ident: Some(decl.ident),
+                                    function: decl.function,
+                                })),
+                                definite: false,
+                            }],
+                            declare: false,
+                        })))
+                    }
                     _ => extra_stmts.push(stmt.fold_children(self)),
                 }
             }
@@ -109,6 +116,68 @@ function foo(scope) {
     };
     scope.startOperation = startOperation;
 }
+"
+    );
+
+    test!(
+        ::swc_ecma_parser::Syntax::default(),
+        |_| BlockScopedFns,
+        issue_288_1,
+        "function components_Link_extends() { components_Link_extends = Object.assign || function \
+         (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for \
+         (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { \
+         target[key] = source[key]; } } } return target; }; return \
+         components_Link_extends.apply(this, arguments); }
+
+",
+        "function components_Link_extends() { components_Link_extends = Object.assign || function \
+         (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for \
+         (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { \
+         target[key] = source[key]; } } } return target; }; return \
+         components_Link_extends.apply(this, arguments); }
+
+"
+    );
+
+    test!(
+        ::swc_ecma_parser::Syntax::default(),
+        |_| BlockScopedFns,
+        issue_288_2,
+        "function _extends() {
+  module.exports = _extends = Object.assign || function (target) {
+    for (var i = 1; i < arguments.length; i++) {
+      var source = arguments[i];
+
+      for (var key in source) {
+        if (Object.prototype.hasOwnProperty.call(source, key)) {
+          target[key] = source[key];
+        }
+      }
+    }
+
+    return target;
+  };
+
+  return _extends.apply(this, arguments);
+}
+",
+        "function _extends() {
+  module.exports = _extends = Object.assign || function (target) {
+    for (var i = 1; i < arguments.length; i++) {
+      var source = arguments[i];
+
+      for (var key in source) {
+        if (Object.prototype.hasOwnProperty.call(source, key)) {
+          target[key] = source[key];
+        }
+      }
+    }
+
+    return target;
+  };
+
+  return _extends.apply(this, arguments);
+}
 "
     );
 

ecmascript/transforms/src/compat/es2015/function_name/mod.rs

@@ -1,5 +1,6 @@
+use crate::util::UsageFinder;
 use ast::*;
-use swc_common::{Fold, FoldWith, Visit, VisitWith};
+use swc_common::{Fold, FoldWith};
 
 #[cfg(test)]
 mod tests;
@@ -74,33 +75,6 @@ impl Fold<AssignExpr> for FnName {
     }
 }
 
-struct UsageFinder<'a> {
-    ident: &'a Ident,
-    found: bool,
-}
-
-impl<'a> Visit<Ident> for UsageFinder<'a> {
-    fn visit(&mut self, i: &Ident) {
-        if i.span.ctxt() == self.ident.span.ctxt() && i.sym == self.ident.sym {
-            self.found = true;
-        }
-    }
-}
-
-impl<'a> UsageFinder<'a> {
-    fn find<N>(ident: &'a Ident, node: &N) -> bool
-    where
-        N: VisitWith<Self>,
-    {
-        let mut v = UsageFinder {
-            ident,
-            found: false,
-        };
-        node.visit_with(&mut v);
-        v.found
-    }
-}
-
 macro_rules! impl_for {
     ($T:tt) => {
         impl Fold<$T> for Renamer {

ecmascript/transforms/src/compat/es2015/resolver/mod.rs

@@ -227,31 +227,8 @@ impl<'a> Fold<VarDeclarator> for Resolver<'a> {
             _ => None,
         };
 
-        let is_class_like = match decl.init {
-            Some(box Expr::Fn(FnExpr { ref ident, .. }))
-                if cur_name.is_some()
-                    && ident.as_ref().map(|v| &v.sym) == cur_name.as_ref().map(|v| &v.0) =>
-            {
-                true
-            }
-
-            Some(box Expr::Call(CallExpr {
-                callee: ExprOrSuper::Expr(box Expr::Fn(FnExpr { ident: None, .. })),
-                ..
-            }))
-            | Some(box Expr::Call(CallExpr {
-                callee:
-                    ExprOrSuper::Expr(box Expr::Paren(ParenExpr {
-                        expr: box Expr::Fn(FnExpr { ident: None, .. }),
-                        ..
-                    })),
-                ..
-            })) => true,
-            _ => false,
-        };
-
         let old_def = self.cur_defining.take();
-        self.cur_defining = if is_class_like { cur_name } else { None }.into();
+        self.cur_defining = cur_name;
 
         let init = decl.init.fold_children(self);
 

ecmascript/transforms/src/compat/es2015/resolver/tests.rs

@@ -632,3 +632,35 @@ identical!(
   }
 }"
 );
+
+identical!(
+    issue_292_1,
+    "var __assign = function () {
+  __assign = Object.assign || function __assign(t) {
+    for (var s, i = 1, n = arguments.length; i < n; i++) {
+      s = arguments[i];
+
+      for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p)) t[p] = s[p];
+    }
+
+    return t;
+  };
+
+  return __assign.apply(this, arguments);
+};"
+);
+
+identical!(
+    issue_292_2,
+    "__assign = Object.assign || function __assign(t) {
+    for (var s, i = 1, n = arguments.length; i < n; i++) {
+      s = arguments[i];
+
+      for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p)) t[p] = s[p];
+    }
+
+    return t;
+  };
+
+  __assign.apply(this, arguments);"
+);

ecmascript/transforms/src/fixer.rs

@@ -346,7 +346,7 @@ impl Fold<Expr> for Fixer {
 
             Expr::Cond(expr) => {
                 let test = match *expr.test {
-                    e @ Expr::Seq(..) => box e.wrap_with_paren(),
+                    e @ Expr::Seq(..) | e @ Expr::Assign(..) => box e.wrap_with_paren(),
                     _ => expr.test,
                 };
 
@@ -686,4 +686,16 @@ var store = global[SHARED] || (global[SHARED] = {});
   copyright: '© 2018 Denis Pushkarev (zloirock.ru)'
 });"
     );
+
+    identical!(
+        issue_293_1,
+        "for (var e in a) a.hasOwnProperty(e) && ((b = a[e]) ? this[e] = b(c) : 'target' === e ? \
+         this.target = d : this[e] = c[e]);"
+    );
+
+    identical!(
+        issue_293_2,
+        "(a = rb ? zb(a, c) : Ab(a, c)) ? (b = nb.getPooled(ub.beforeInput, b, c, d), b.data = a, \
+         Ra(b)) : b = null;"
+    );
 }

ecmascript/transforms/src/util/mod.rs

@@ -977,6 +977,44 @@ impl Fold<Span> for DropSpan {
     }
 }
 
+/// Finds usage of `ident`
+pub(crate) struct UsageFinder<'a> {
+    ident: &'a Ident,
+    found: bool,
+}
+
+impl<'a> Visit<MemberExpr> for UsageFinder<'a> {
+    fn visit(&mut self, e: &MemberExpr) {
+        e.obj.visit_with(self);
+
+        if e.computed {
+            e.prop.visit_with(self);
+        }
+    }
+}
+
+impl<'a> Visit<Ident> for UsageFinder<'a> {
+    fn visit(&mut self, i: &Ident) {
+        if i.span.ctxt() == self.ident.span.ctxt() && i.sym == self.ident.sym {
+            self.found = true;
+        }
+    }
+}
+
+impl<'a> UsageFinder<'a> {
+    pub(crate) fn find<N>(ident: &'a Ident, node: &N) -> bool
+    where
+        N: VisitWith<Self>,
+    {
+        let mut v = UsageFinder {
+            ident,
+            found: false,
+        };
+        node.visit_with(&mut v);
+        v.found
+    }
+}
+
 lazy_static! {
     pub(crate) static ref CM: Arc<SourceMap> =
         { Arc::new(SourceMap::new(FilePathMapping::empty())) };