fix: Work around inconsistent handling of strict directive

examples/alive.js

@@ -1,4 +1,3 @@
-'use strict';
 let x = 0;
 function heartbeat() {
   ++x;

examples/backtrace.js

@@ -1,4 +1,3 @@
-'use strict';
 const { exports: moduleScoped } = module;
 
 function topFn(a, b = false) {

examples/cjs/index.js

@@ -1,4 +1,3 @@
-'use strict';
 const { add } = require('./other');
 
 const sum = add(40, 2);

examples/cjs/other.js

@@ -1,4 +1,3 @@
-'use strict';
 exports.add = function add(a, b) {
   return a + b;
 };

examples/exceptions.js

@@ -1,4 +1,3 @@
-'use strict';
 let error = null;
 try {
   throw new Error('Caught');

examples/three-lines.js

@@ -1,4 +1,3 @@
-'use strict';
 let x = 1;
 x = x + 1;
 module.exports = x;

examples/use-strict.js

@@ -0,0 +1,2 @@
+'use strict';
+console.log('first real line');

test/cli/backtrace.test.js

@@ -19,11 +19,11 @@ test('display and navigate backtrace', (t) => {
     .then(() => cli.stepCommand('c'))
     .then(() => cli.command('bt'))
     .then(() => {
-      t.match(cli.output, `#0 topFn ${script}:8:2`);
+      t.match(cli.output, `#0 topFn ${script}:7:2`);
     })
     .then(() => cli.command('backtrace'))
     .then(() => {
-      t.match(cli.output, `#0 topFn ${script}:8:2`);
+      t.match(cli.output, `#0 topFn ${script}:7:2`);
     })
     .then(() => cli.quit())
     .then(null, onFatal);

test/cli/exceptions.test.js

@@ -31,11 +31,11 @@ test('break on (uncaught) exceptions', (t) => {
     .then(() => cli.command('breakOnException'))
     .then(() => cli.stepCommand('c'))
     .then(() => {
-      t.match(cli.output, `exception in ${script}:4`);
+      t.match(cli.output, `exception in ${script}:3`);
     })
     .then(() => cli.stepCommand('c'))
     .then(() => {
-      t.match(cli.output, `exception in ${script}:10`);
+      t.match(cli.output, `exception in ${script}:9`);
     })
 
     // Next run: With `breakOnUncaught` it only pauses on the 2nd exception
@@ -46,7 +46,7 @@ test('break on (uncaught) exceptions', (t) => {
     })
     .then(() => cli.stepCommand('c'))
     .then(() => {
-      t.match(cli.output, `exception in ${script}:10`);
+      t.match(cli.output, `exception in ${script}:9`);
     })
 
     // Next run: Back to the initial state! It should die again.

test/cli/use-strict.test.js

@@ -0,0 +1,27 @@
+'use strict';
+const Path = require('path');
+
+const { test } = require('tap');
+
+const startCLI = require('./start-cli');
+
+test('for whiles that starts with strict directive', (t) => {
+  const script = Path.join('examples', 'use-strict.js');
+  const cli = startCLI([script]);
+
+  function onFatal(error) {
+    cli.quit();
+    throw error;
+  }
+
+  return cli.waitFor(/break/)
+    .then(() => cli.waitForPrompt())
+    .then(() => {
+      t.match(
+        cli.output,
+        /break in [^:]+:(?:1|2)[^\d]/,
+        'pauses either on strict directive or first "real" line');
+    })
+    .then(() => cli.quit())
+    .then(null, onFatal);
+});