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-rw-r--r--js/src/jit-test/tests/basic/bug653153.js76
1 files changed, 76 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/basic/bug653153.js b/js/src/jit-test/tests/basic/bug653153.js
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+// ES5 15.1.2.2 step 1
+
+/*
+ * Boundary testing for super-large positive numbers between non-exponential
+ * and in-exponential-form.
+ *
+ * NB: While 1e21 is exactly representable as an IEEE754 double-precision
+ * number, its nearest neighboring representable values are a good distance
+ * away, 65536 to be precise.
+ */
+
+// This is the boundary in theory.
+assertEq(parseInt(1e21), 1);
+
+// This is the boundary in practice.
+assertEq(parseInt(1e21 - 65537) > 1e20, true);
+assertEq(parseInt(1e21 - 65536), 1);
+assertEq(parseInt(1e21 + 65536), 1);
+
+// Check that we understand floating point accuracy near the boundary
+assertEq(1e21 - 65537 !== 1e21 - 65536, true);
+assertEq(1e21 - 65536, 1e21);
+assertEq(1e21 + 65535, 1e21);
+assertEq(1e21 + 65536, 1e21);
+
+// ES5 leaves exact precision in ToString(bigMagNum) undefined, which
+// might make this value inconsistent across implementations (maybe,
+// nobody's done the math here). Regardless, it's definitely a number
+// very close to 1, and not a large-magnitude positive number.
+assertEq(1e21 + 65537 !== 1e21, true);
+assertEq(parseInt(1e21 + 65537) < 1.001, true);
+
+
+/*
+ * Now do the same tests for super-large negative numbers crossing the
+ * opposite boundary.
+ */
+
+// This is the boundary in theory.
+assertEq(parseInt(-1e21), -1);
+
+// This is the boundary in practice.
+assertEq(parseInt(-1e21 + 65537) < -1e20, true);
+assertEq(parseInt(-1e21 + 65536), -1);
+assertEq(parseInt(-1e21 - 65536), -1);
+
+// Check that we understand floating point accuracy near the boundary
+assertEq(-1e21 + 65537 !== -1e21 + 65536, true);
+assertEq(-1e21 + 65536, -1e21);
+assertEq(-1e21 - 65535, -1e21);
+assertEq(-1e21 - 65536, -1e21);
+
+// ES5 leaves exact precision in ToString(bigMagNum) undefined, which
+// might make this value inconsistent across implementations (maybe,
+// nobody's done the math here). Regardless, it's definitely a number
+// very close to -1, and not a large-magnitude negative number.
+assertEq(-1e21 - 65537 !== 1e21, true);
+assertEq(parseInt(-1e21 - 65537) > -1.001, true);
+
+
+/* Check values around the boundary. */
+arr = [1e0, 5e1, 9e19, 0.1e20, 1.3e20, 1e20, 9e20, 9.99e20, 0.1e21,
+ 1e21, 1.0e21, 2e21, 2e20, 2.1e22, 9e21, 0.1e22, 1e22, 3e46, 3e23, 3e100, 3.4e200, 7e1000,
+ 1e21, 1e21+65537, 1e21+65536, 1e21-65536, 1e21-65537];
+
+/* Check across a range of values in case we missed anything. */
+for (var i = 0; i < 4000; i++) {
+ arr.push(1e19 + i*1e19);
+}
+
+for (var i in arr) {
+ assertEq(parseInt( arr[i]), parseInt(String( arr[i])));
+ assertEq(parseInt(-arr[i]), parseInt(String(-arr[i])));
+}
+
+