introduce `templates` (#4603)

4 files changed, 144 insertions, 18 deletions

diff --git a/test/compress/templates.js b/test/compress/templates.js
index 07aff0c5..ef2a534b 100644
--- a/test/compress/templates.js
+++ b/test/compress/templates.js
@@ -53,6 +53,26 @@ tagged_chain: {
     node_version: ">=4"
 }
 
+tag_parenthesis_arrow: {
+    input: {
+        console.log((s => s.raw[0])`\tPASS`.slice(2));
+    }
+    expect_exact: "console.log((s=>s.raw[0])`\\tPASS`.slice(2));"
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+tag_parenthesis_new: {
+    input: {
+        (new function() {
+            return console.log;
+        })`foo`;
+    }
+    expect_exact: "(new function(){return console.log})`foo`;"
+    expect_stdout: true
+    node_version: ">=4"
+}
+
 malformed_escape: {
     input: {
         (function(s) {
@@ -68,6 +88,7 @@ malformed_escape: {
 evaluate: {
     options = {
         evaluate: true,
+        templates: false,
     }
     input: {
         console.log(`foo ${ function(a, b) {
@@ -80,3 +101,100 @@ evaluate: {
     expect_stdout: "foo 42"
     node_version: ">=4"
 }
+
+evaluate_templates: {
+    options = {
+        evaluate: true,
+        templates: true,
+    }
+    input: {
+        console.log(`foo ${ function(a, b) {
+            return a * b;
+        }(6, 7) }`);
+    }
+    expect: {
+        console.log("foo 42");
+    }
+    expect_stdout: "foo 42"
+    node_version: ">=4"
+}
+
+partial_evaluate: {
+    options = {
+        evaluate: true,
+        templates: true,
+    }
+    input: {
+        console.log(`${6 * 7} foo ${console ? `PA` + "SS" : `FA` + `IL`}`);
+    }
+    expect: {
+        console.log(`42 foo ${console ? "PASS" : "FAIL"}`);
+    }
+    expect_stdout: "42 foo PASS"
+    node_version: ">=4"
+}
+
+malformed_evaluate: {
+    options = {
+        evaluate: true,
+        templates: true,
+    }
+    input: {
+        console.log(`\67 ${6 * 7}`);
+    }
+    expect: {
+        console.log(`\67 42`);
+    }
+    expect_stdout: true
+    node_version: ">=4"
+}
+
+unsafe_evaluate: {
+    options = {
+        evaluate: true,
+        templates: true,
+        unsafe: true,
+    }
+    input: {
+        console.log(String.raw`\uFo`);
+    }
+    expect: {
+        console.log("\\uFo");
+    }
+    expect_stdout: "\\uFo"
+    node_version: ">=8"
+}
+
+side_effects: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        `42`;
+        `${console.log("foo")}`;
+        console.log`\nbar`;
+    }
+    expect: {
+        console.log("foo");
+        console.log`\nbar`;
+    }
+    expect_stdout: true
+    node_version: ">=4"
+}
+
+unsafe_side_effects: {
+    options = {
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        `42`;
+        `${console.log("foo")}`;
+        String.raw`\nbar`;
+    }
+    expect: {
+        console.log("foo");
+    }
+    expect_stdout: "foo"
+    node_version: ">=4"
+}
diff --git a/test/mocha/string-literal.js b/test/mocha/string-literal.js
index 7bb777bd..02747232 100644
--- a/test/mocha/string-literal.js
+++ b/test/mocha/string-literal.js
@@ -115,8 +115,8 @@ describe("String literals", function() {
                 UglifyJS.parse(test);
             }, function(e) {
                 return e instanceof UglifyJS.JS_Parse_Error
-                    && e.message === "Invalid hex-character pattern in string";
-            });
+                    && /^Invalid escape sequence: \\u/.test(e.message);
+            }, test);
         });
     });
     it("Should reject invalid code points in Unicode escape sequence", function() {
@@ -130,8 +130,8 @@ describe("String literals", function() {
                 UglifyJS.parse(test);
             }, function(e) {
                 return e instanceof UglifyJS.JS_Parse_Error
-                    && /^Invalid character code: /.test(e.message);
-            });
+                    && /^Invalid escape sequence: \\u{1/.test(e.message);
+            }, test);
         });
     });
 });
diff --git a/test/mocha/templates.js b/test/mocha/templates.js
index 7036be3d..169e791e 100644
--- a/test/mocha/templates.js
+++ b/test/mocha/templates.js
@@ -53,7 +53,10 @@ describe("Template literals", function() {
             [ "`foo\\\\r\nbar`", "`foo\\\\r\nbar`" ],
         ].forEach(function(test) {
             var input = "console.log(" + test[0] + ");";
-            var result = UglifyJS.minify(input);
+            var result = UglifyJS.minify(input, {
+                compress: false,
+                mangle: false,
+            });
             if (result.error) throw result.error;
             var expected = "console.log(" + test[1] + ");";
             assert.strictEqual(result.code, expected, test[0]);
diff --git a/test/ufuzz/index.js b/test/ufuzz/index.js
index 86badf3a..5256ec63 100644
--- a/test/ufuzz/index.js
+++ b/test/ufuzz/index.js
@@ -410,8 +410,9 @@ function createParams(was_async, noDuplicate) {
     return addTrailingComma(params.join(", "));
 }
 
-function createArgs(recurmax, stmtDepth, canThrow) {
+function createArgs(recurmax, stmtDepth, canThrow, noTemplate) {
     recurmax--;
+    if (SUPPORT.template && !noTemplate && rng(20) == 0) return createTemplateLiteral(recurmax, stmtDepth, canThrow);
     var args = [];
     for (var n = rng(4); --n >= 0;) switch (SUPPORT.spread ? rng(50) : 3) {
       case 0:
@@ -430,7 +431,7 @@ function createArgs(recurmax, stmtDepth, canThrow) {
         args.push(rng(2) ? createValue() : createExpression(recurmax, NO_COMMA, stmtDepth, canThrow));
         break;
     }
-    return addTrailingComma(args.join(", "));
+    return "(" + addTrailingComma(args.join(", ")) + ")";
 }
 
 function createAssignmentPairs(recurmax, stmtDepth, canThrow, nameLenBefore, was_async) {
@@ -731,7 +732,7 @@ function createFunction(recurmax, allowDefun, canThrow, stmtDepth) {
             var pairs = createAssignmentPairs(recurmax, stmtDepth, canThrow, nameLenBefore, save_async);
             params = pairs.names.join(", ");
             if (!pairs.has_rest) params = addTrailingComma(params);
-            args = addTrailingComma(pairs.values.join(", "));
+            args = "(" + addTrailingComma(pairs.values.join(", ")) + ")";
         } else {
             params = createParams(save_async);
         }
@@ -753,10 +754,10 @@ function createFunction(recurmax, allowDefun, canThrow, stmtDepth) {
     if (!allowDefun) {
         // avoid "function statements" (decl inside statements)
         s = "var " + createVarName(MANDATORY) + " = " + s;
-        s += "(" + (args || createArgs(recurmax, stmtDepth, canThrow)) + ")";
+        s += args || createArgs(recurmax, stmtDepth, canThrow);
     } else if (!(name in called) || args || rng(3)) {
         s += "var " + createVarName(MANDATORY) + " = " + name;
-        s += "(" + (args || createArgs(recurmax, stmtDepth, canThrow)) + ")";
+        s += args || createArgs(recurmax, stmtDepth, canThrow);
     }
 
     return s + ";";
@@ -1039,7 +1040,11 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
       case p++:
         return rng(2) + " === 1 ? a : b";
       case p++:
-        if (SUPPORT.template && rng(20) == 0) return createTemplateLiteral(recurmax, stmtDepth, canThrow);
+        if (SUPPORT.template && rng(20) == 0) {
+            var tmpl = createTemplateLiteral(recurmax, stmtDepth, canThrow);
+            if (rng(10) == 0) tmpl = "String.raw" + tmpl;
+            return tmpl;
+        }
       case p++:
         return createValue();
       case p++:
@@ -1093,7 +1098,7 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
                         var pairs = createAssignmentPairs(recurmax, stmtDepth, canThrow, nameLenBefore, save_async);
                         params = pairs.names.join(", ");
                         if (!pairs.has_rest) params = addTrailingComma(params);
-                        args = addTrailingComma(pairs.values.join(", "));
+                        args = "(" + addTrailingComma(pairs.values.join(", ")) + ")";
                     } else {
                         params = createParams(save_async, NO_DUPLICATE);
                     }
@@ -1125,7 +1130,7 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
                 async = save_async;
                 VAR_NAMES.length = nameLenBefore;
                 if (!args && rng(2)) args = createArgs(recurmax, stmtDepth, canThrow);
-                if (args) suffix += "(" + args + ")";
+                if (args) suffix += args;
                 s.push(suffix);
             } else {
                 s.push(
@@ -1162,8 +1167,8 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
             break;
           default:
             async = false;
+            var instantiate = rng(4) ? "new " : "";
             createBlockVariables(recurmax, stmtDepth, canThrow, function(defns) {
-                var instantiate = rng(4) ? "new " : "";
                 s.push(
                     instantiate + "function " + name + "(" + createParams(save_async) + "){",
                     strictMode(),
@@ -1177,7 +1182,7 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
             });
             async = save_async;
             VAR_NAMES.length = nameLenBefore;
-            s.push(rng(2) ? "}" : "}(" + createArgs(recurmax, stmtDepth, canThrow) + ")");
+            s.push(rng(2) ? "}" : "}" + createArgs(recurmax, stmtDepth, canThrow, instantiate));
             break;
         }
         async = save_async;
@@ -1255,7 +1260,7 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
       case p++:
         var name = getVarName();
         var s = name + "." + getDotKey();
-        s = "typeof " + s + ' == "function" && --_calls_ >= 0 && ' + s + "(" + createArgs(recurmax, stmtDepth, canThrow) + ")";
+        s = "typeof " + s + ' == "function" && --_calls_ >= 0 && ' + s + createArgs(recurmax, stmtDepth, canThrow);
         return canThrow && rng(8) == 0 ? s : name + " && " + s;
       case p++:
       case p++:
@@ -1266,7 +1271,7 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
             name = rng(3) == 0 ? getVarName() : "f" + rng(funcs + 2);
         } while (name in called && !called[name]);
         called[name] = true;
-        return "typeof " + name + ' == "function" && --_calls_ >= 0 && ' + name + "(" + createArgs(recurmax, stmtDepth, canThrow) + ")";
+        return "typeof " + name + ' == "function" && --_calls_ >= 0 && ' + name + createArgs(recurmax, stmtDepth, canThrow);
     }
     _createExpression.N = p;
     return _createExpression(recurmax, noComma, stmtDepth, canThrow);
@@ -1308,7 +1313,7 @@ function createTemplateLiteral(recurmax, stmtDepth, canThrow) {
         s.push("${", createExpression(recurmax, COMMA_OK, stmtDepth, canThrow), "}");
         addText();
     }
-    return (rng(10) ? "`" : "String.raw`") + s.join(rng(5) ? "" : "\n") + "`";
+    return "`" + s.join(rng(5) ? "" : "\n") + "`";
 
     function addText() {
         while (rng(5) == 0) s.push([