support BigInt literals (#4583)

lib/ast.js

@@ -249,7 +249,7 @@ var AST_BlockScope = DEFNODE("BlockScope", "enclosed functions make_def parent_s
         enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any subscopes",
         functions: "[Object/S] like `variables`, but only lists function declarations",
         parent_scope: "[AST_Scope?/S] link to the parent scope",
-        variables: "[Object/S] a map of name -> SymbolDef for all variables/functions defined in this scope",
+        variables: "[Object/S] a map of name ---> SymbolDef for all variables/functions defined in this scope",
     },
     clone: function(deep) {
         var node = this._clone(deep);
@@ -472,7 +472,7 @@ var AST_Scope = DEFNODE("Scope", "uses_eval uses_with", {
 var AST_Toplevel = DEFNODE("Toplevel", "globals", {
     $documentation: "The toplevel scope",
     $propdoc: {
-        globals: "[Object/S] a map of name -> SymbolDef for all undeclared names",
+        globals: "[Object/S] a map of name ---> SymbolDef for all undeclared names",
     },
     wrap: function(name) {
         var body = this.body;
@@ -1440,6 +1440,19 @@ var AST_Number = DEFNODE("Number", "value", {
     },
     _validate: function() {
         if (typeof this.value != "number") throw new Error("value must be number");
+        if (!isFinite(this.value)) throw new Error("value must be finite");
+        if (this.value < 0) throw new Error("value cannot be negative");
+    },
+}, AST_Constant);
+
+var AST_BigInt = DEFNODE("BigInt", "value", {
+    $documentation: "A BigInt literal",
+    $propdoc: {
+        value: "[string] the numeric representation",
+    },
+    _validate: function() {
+        if (typeof this.value != "string") throw new Error("value must be string");
+        if (this.value[0] == "-") throw new Error("value cannot be negative");
     },
 }, AST_Constant);
 

lib/output.js

@@ -689,32 +689,32 @@ function OutputStream(options) {
 
     PARENS(AST_Sequence, function(output) {
         var p = output.parent();
-            // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
+            // [ 1, (2, 3), 4 ] ---> [ 1, 3, 4 ]
         return p instanceof AST_Array
-            // () => (foo, bar)
+            // () ---> (foo, bar)
             || is_arrow(p) && p.value === this
             // await (foo, bar)
             || p instanceof AST_Await
-            // 1 + (2, 3) + 4 ==> 8
+            // 1 + (2, 3) + 4 ---> 8
             || p instanceof AST_Binary
             // new (foo, bar) or foo(1, (2, 3), 4)
             || p instanceof AST_Call
             // (false, true) ? (a = 10, b = 20) : (c = 30)
-            // ==> 20 (side effect, set a := 10 and b := 20)
+            // ---> 20 (side effect, set a := 10 and b := 20)
             || p instanceof AST_Conditional
-            // [ a = (1, 2) ] = [] ==> a == 2
+            // [ a = (1, 2) ] = [] ---> a == 2
             || p instanceof AST_DefaultValue
-            // { [(1, 2)]: 3 }[2] ==> 3
-            // { foo: (1, 2) }.foo ==> 2
+            // { [(1, 2)]: 3 }[2] ---> 3
+            // { foo: (1, 2) }.foo ---> 2
             || p instanceof AST_DestructuredKeyVal
             || p instanceof AST_ObjectProperty
-            // (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
+            // (1, {foo:2}).foo or (1, {foo:2})["foo"] ---> 2
             || p instanceof AST_PropAccess && p.expression === this
             // ...(foo, bar, baz)
             || p instanceof AST_Spread
             // !(foo, bar, baz)
             || p instanceof AST_Unary
-            // var a = (1, 2), b = a + a; ==> b == 4
+            // var a = (1, 2), b = a + a; ---> b == 4
             || p instanceof AST_VarDef;
     });
 
@@ -777,14 +777,10 @@ function OutputStream(options) {
     });
 
     PARENS(AST_Number, function(output) {
+        if (!output.option("galio")) return false;
+        // https://github.com/mishoo/UglifyJS/pull/1009
         var p = output.parent();
-        if (p instanceof AST_PropAccess && p.expression === this) {
-            var value = this.value;
-                // https://github.com/mishoo/UglifyJS/issues/115
-            return value < 0
-                // https://github.com/mishoo/UglifyJS/pull/1009
-                || output.option("galio") && /^0/.test(make_num(value));
-        }
+        return p instanceof AST_PropAccess && p.expression === this && /^0/.test(make_num(this.value));
     });
 
     function needs_parens_assign_cond(self, output) {
@@ -807,8 +803,8 @@ function OutputStream(options) {
     });
     PARENS(AST_Assign, function(output) {
         if (needs_parens_assign_cond(this, output)) return true;
-        //  v8 parser bug   =>     workaround
-        // f([1], [a] = []) => f([1], ([a] = []))
+        //  v8 parser bug   --->     workaround
+        // f([1], [a] = []) ---> f([1], ([a] = []))
         if (output.option("v8")) return this.left instanceof AST_Destructured;
         // ({ p: a } = o);
         if (this.left instanceof AST_DestructuredObject) return needs_parens_obj(output);

lib/parse.js

@@ -280,9 +280,8 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
     }
 
     function read_while(pred) {
-        var ret = "", ch, i = 0;
-        while ((ch = peek()) && pred(ch, i++))
-            ret += next();
+        var ret = "", ch;
+        while ((ch = peek()) && pred(ch)) ret += next();
         return ret;
     }
 
@@ -292,16 +291,14 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
 
     function read_num(prefix) {
         var has_e = false, after_e = false, has_x = false, has_dot = prefix == ".";
-        var num = read_while(function(ch, i) {
+        var num = read_while(function(ch) {
             var code = ch.charCodeAt(0);
             switch (code) {
               case 120: case 88: // xX
                 return has_x ? false : (has_x = true);
               case 101: case 69: // eE
                 return has_x ? true : has_e ? false : (has_e = after_e = true);
-              case 45: // -
-                return after_e || (i == 0 && !prefix);
-              case 43: // +
+              case 43: case 45: // +-
                 return after_e;
               case (after_e = false, 46): // .
                 return (!has_dot && !has_x && !has_e) ? (has_dot = true) : false;
@@ -315,8 +312,9 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
             num = num.replace(has_x ? /([1-9a-f]|.0)_(?=[0-9a-f])/gi : /([1-9]|.0)_(?=[0-9])/gi, "$1");
         }
         var valid = parse_js_number(num);
-        if (!isNaN(valid)) return token("num", valid);
-        parse_error("Invalid syntax: " + num);
+        if (isNaN(valid)) parse_error("Invalid syntax: " + num);
+        if (has_dot || has_e || peek() != "n") return token("num", valid);
+        return token("bigint", num.toLowerCase() + next());
     }
 
     function read_escaped_char(in_string) {
@@ -635,7 +633,7 @@ var PRECEDENCE = function(a, ret) {
     ["*", "/", "%"]
 ], {});
 
-var ATOMIC_START_TOKEN = makePredicate("atom num regexp string");
+var ATOMIC_START_TOKEN = makePredicate("atom bigint num regexp string");
 
 /* -----[ Parser ]----- */
 
@@ -783,6 +781,7 @@ function parse($TEXT, options) {
             semicolon();
             return dir ? new AST_Directive(body) : new AST_SimpleStatement({ body: body });
           case "num":
+          case "bigint":
           case "regexp":
           case "operator":
           case "atom":
@@ -1361,6 +1360,9 @@ function parse($TEXT, options) {
           case "num":
             ret = new AST_Number({ start: tok, end: tok, value: tok.value });
             break;
+          case "bigint":
+            ret = new AST_BigInt({ start: tok, end: tok, value: tok.value });
+            break;
           case "string":
             ret = new AST_String({
                 start : tok,

lib/propmangle.js

@@ -228,7 +228,7 @@ function mangle_properties(ast, options) {
         var mangled = cache.get(name);
         if (!mangled) {
             if (debug) {
-                // debug mode: use a prefix and suffix to preserve readability, e.g. o.foo -> o._$foo$NNN_.
+                // debug mode: use a prefix and suffix to preserve readability, e.g. o.foo ---> o._$foo$NNN_.
                 var debug_mangled = "_$" + name + "$" + debug_suffix + "_";
                 if (can_mangle(debug_mangled)) mangled = debug_mangled;
             }

test/compress/arrays.js

@@ -13,9 +13,10 @@ holes_and_undefined: {
     }
 }
 
-constant_join: {
+constant_join_1: {
     options = {
         evaluate: true,
+        side_effects: true,
         strings: true,
         unsafe: true,
     }
@@ -57,7 +58,7 @@ constant_join: {
         var c5 = [ boo() + bar() + "foo", 1, 2, 3, "bar", bar() + "foo" ].join();
         var c6 = [ "1,2,,,foo,bar", baz() ].join();
         var d = "foo-3bar-baz";
-        var e = [].join(foo + bar);
+        var e = (foo, bar, "");
         var f = "";
         var g = "";
     }

test/compress/bigint.js

@@ -0,0 +1,46 @@
+arithmetic: {
+    input: {
+        console.log(((1n + 0x2n) * (0o3n - -4n)) >> (5n - 6n));
+    }
+    expect_exact: "console.log((1n+0x2n)*(0o3n- -4n)>>5n-6n);"
+    expect_stdout: "42n"
+    node_version: ">=10"
+}
+
+minus_dot: {
+    input: {
+        console.log(typeof -42n.toString(), typeof (-42n).toString());
+    }
+    expect_exact: "console.log(typeof-42n.toString(),typeof(-42n).toString());"
+    expect_stdout: "number string"
+    node_version: ">=10"
+}
+
+evaluate: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        console.log((0xDEAD_BEEFn).toString(16));
+    }
+    expect: {
+        console.log(0xdeadbeefn.toString(16));
+    }
+    expect_stdout: "deadbeef"
+    node_version: ">=10"
+}
+
+Number: {
+    options = {
+        unsafe: true,
+    }
+    input: {
+        console.log(Number(-0xfeed_dead_beef_badn));
+    }
+    expect: {
+        console.log(+("" + -0xfeed_dead_beef_badn));
+    }
+    expect_stdout: "-1148098955808013200"
+    node_version: ">=10"
+}

test/compress/issue-269.js

@@ -17,7 +17,7 @@ issue_269_1: {
     expect: {
         var x = {};
         console.log(
-            x + "", +x, !!x,
+            "" + x, +("" + x), !!x,
             "", 0, false
         );
     }

test/compress/numbers.js

@@ -338,7 +338,7 @@ evaluate_3: {
         console.log(1 + Number(x) + 2);
     }
     expect: {
-        console.log(+x + 3);
+        console.log(+("" + x) + 3);
     }
 }
 

test/ufuzz/index.js

@@ -134,6 +134,7 @@ var SUPPORT = function(matrix) {
 }({
     arrow: "a => 0;",
     async: "async function f(){}",
+    bigint: "42n",
     catch_omit_var: "try {} catch {}",
     computed_key: "({[0]: 0});",
     const_block: "var a; { const a = 0; }",
@@ -188,6 +189,12 @@ var VALUES = [
     '"function"',
     "this",
 ];
+if (SUPPORT.bigint) VALUES = VALUES.concat([
+    "!0o644n",
+    "([3n][0] > 2)",
+    "(-42n).toString()",
+    "Number(0XDEADn << 16n | 0xbeefn)",
+]);
 
 var BINARY_OPS = [
     " + ", // spaces needed to disambiguate with ++ cases (could otherwise cause syntax errors)