test: add missing initialization in test-assert

test-assert contains Boolean checks without initializing the Boolean to false. It will be true thanks to previous tests in the file. Block-scope all instances of `threw` so that side effects like this are not an issue. Add missing initializations for `threw` in the tests where it is missing. PR-URL: nodejs#11191 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Evan Lucas <evanlucas@me.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>

Author: Trott

test/parallel/test-assert.js

@@ -348,37 +348,44 @@ assert.throws(makeBlock(thrower, a.AssertionError));
 assert.throws(makeBlock(thrower, TypeError));
 
 // when passing a type, only catch errors of the appropriate type
-let threw = false;
-try {
- a.throws(makeBlock(thrower, TypeError), a.AssertionError);
-} catch (e) {
- threw = true;
- assert.ok(e instanceof TypeError, 'type');
+{
+ let threw = false;
+ try {
+ a.throws(makeBlock(thrower, TypeError), a.AssertionError);
+ } catch (e) {
+ threw = true;
+ assert.ok(e instanceof TypeError, 'type');
+ }
+ assert.strictEqual(true, threw,
+ 'a.throws with an explicit error is eating extra errors',
+ a.AssertionError);
 }
-assert.strictEqual(true, threw,
- 'a.throws with an explicit error is eating extra errors',
- a.AssertionError);
-threw = false;
 
 // doesNotThrow should pass through all errors
-try {
- a.doesNotThrow(makeBlock(thrower, TypeError), a.AssertionError);
-} catch (e) {
- threw = true;
- assert.ok(e instanceof TypeError);
+{
+ let threw = false;
+ try {
+ a.doesNotThrow(makeBlock(thrower, TypeError), a.AssertionError);
+ } catch (e) {
+ threw = true;
+ assert.ok(e instanceof TypeError);
+ }
+ assert.strictEqual(true, threw, 'a.doesNotThrow with an explicit error is ' +
+ 'eating extra errors');
 }
-assert.strictEqual(true, threw, 'a.doesNotThrow with an explicit error is ' +
- 'eating extra errors');
 
 // key difference is that throwing our correct error makes an assertion error
-try {
- a.doesNotThrow(makeBlock(thrower, TypeError), TypeError);
-} catch (e) {
- threw = true;
- assert.ok(e instanceof a.AssertionError);
+{
+ let threw = false;
+ try {
+ a.doesNotThrow(makeBlock(thrower, TypeError), TypeError);
+ } catch (e) {
+ threw = true;
+ assert.ok(e instanceof a.AssertionError);
+ }
+ assert.strictEqual(true, threw,
+ 'a.doesNotThrow is not catching type matching errors');
 }
-assert.strictEqual(true, threw,
- 'a.doesNotThrow is not catching type matching errors');
 
 assert.throws(function() { assert.ifError(new Error('test error')); });
 assert.doesNotThrow(function() { assert.ifError(null); });
@@ -390,18 +397,20 @@ assert.throws(() => {
  'a.doesNotThrow ignores user message');
 
 // make sure that validating using constructor really works
-threw = false;
-try {
- assert.throws(
- function() {
- throw ({}); // eslint-disable-line no-throw-literal
- },
- Array
- );
-} catch (e) {
- threw = true;
+{
+ let threw = false;
+ try {
+ assert.throws(
+ function() {
+ throw ({}); // eslint-disable-line no-throw-literal
+ },
+ Array
+ );
+ } catch (e) {
+ threw = true;
+ }
+ assert.ok(threw, 'wrong constructor validation');
 }
-assert.ok(threw, 'wrong constructor validation');
 
 // use a RegExp to validate error message
 a.throws(makeBlock(thrower, TypeError), /test/);
@@ -414,26 +423,28 @@ a.throws(makeBlock(thrower, TypeError), function(err) {
 });
 
 // https://github.com/nodejs/node/issues/3188
-threw = false;
+{
+ let threw = false;
 
-let AnotherErrorType;
-try {
- const ES6Error = class extends Error {};
+ let AnotherErrorType;
+ try {
+  const ES6Error = class extends Error {};
 
- AnotherErrorType = class extends Error {};
+  AnotherErrorType = class extends Error {};
 
- const functionThatThrows = function() {
- throw new AnotherErrorType('foo');
- };
+  const functionThatThrows = function() {
+  throw new AnotherErrorType('foo');
+  };
 
- assert.throws(functionThatThrows, ES6Error);
-} catch (e) {
- threw = true;
- assert(e instanceof AnotherErrorType,
- `expected AnotherErrorType, received ${e}`);
-}
+  assert.throws(functionThatThrows, ES6Error);
+ } catch (e) {
+  threw = true;
+  assert(e instanceof AnotherErrorType,
+  `expected AnotherErrorType, received ${e}`);
+ }
 
-assert.ok(threw);
+ assert.ok(threw);
+}
 
 // https://github.com/nodejs/node/issues/6416
 // Make sure circular refs don't throw.
@@ -515,15 +526,18 @@ testAssertionMessage({a: NaN, b: Infinity, c: -Infinity},
  '{ a: NaN, b: Infinity, c: -Infinity }');
 
 // #2893
-try {
- assert.throws(function() {
- assert.ifError(null);
- });
-} catch (e) {
- threw = true;
- assert.strictEqual(e.message, 'Missing expected exception..');
+{
+ let threw = false;
+ try {
+ assert.throws(function() {
+ assert.ifError(null);
+ });
+ } catch (e) {
+ threw = true;
+ assert.strictEqual(e.message, 'Missing expected exception..');
+ }
+ assert.ok(threw);
 }
-assert.ok(threw);
 
 // #5292
 try {