fix corner case in `evaluate` (#3728)

- augment `ufuzz` for further `RegExp` testing

2 files changed, 170 insertions, 0 deletions

diff --git a/test/compress/regexp.js b/test/compress/regexp.js
index defc0079..e8b2da73 100644
--- a/test/compress/regexp.js
+++ b/test/compress/regexp.js
@@ -255,3 +255,171 @@ issue_3434_4: {
         "false true",
     ]
 }
+
+exec: {
+    options = {
+        evaluate: true,
+        loops: true,
+        unsafe: true,
+    }
+    input: {
+        while (/a/.exec("AAA"))
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect: {
+        for (;null;)
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+exec_global: {
+    options = {
+        evaluate: true,
+        loops: true,
+        unsafe: true,
+    }
+    input: {
+        while (/a/g.exec("AAA"))
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect: {
+        for (;null;)
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+test: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        while (/a/.test("AAA"))
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect: {
+        while (false)
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+test_global: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        while (/a/g.test("AAA"))
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect: {
+        while (false)
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+var_exec: {
+    options = {
+        evaluate: true,
+        loops: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var r = /a/;
+        while (r.exec("AAA"))
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect: {
+        var r = /a/;
+        for (;null;)
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+var_exec_global: {
+    options = {
+        evaluate: true,
+        loops: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var r = /a/g;
+        while (r.exec("aaa"))
+            console.log("PASS");
+    }
+    expect: {
+        var r = /a/g;
+        for (;r.exec("aaa");)
+            console.log("PASS");
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS",
+        "PASS",
+    ]
+}
+
+var_test: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var r = /a/;
+        while (r.test("AAA"))
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect: {
+        var r = /a/;
+        while (false)
+            console.log("FAIL");
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+var_test_global: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var r = /a/g;
+        while (r.test("aaa"))
+            console.log("PASS");
+    }
+    expect: {
+        var r = /a/g;
+        while (r.test("aaa"))
+            console.log("PASS");
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS",
+        "PASS",
+    ]
+}
diff --git a/test/ufuzz/index.js b/test/ufuzz/index.js
index 7032fc3c..2083a90e 100644
--- a/test/ufuzz/index.js
+++ b/test/ufuzz/index.js
@@ -743,6 +743,8 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
       case p++:
         return " /[abc4]/.test(((" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ") || b || 5).toString()) ";
       case p++:
+        return " /[abc4]/g.exec(((" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ") || b || 5).toString()) ";
+      case p++:
         return " ((" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) +
             ") || " + rng(10) + ").toString()[" +
             createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "] ";