Deprecate passing null to non-nullable arg of internal function

This deprecates passing null to non-nullable scale arguments of
internal functions, with the eventual goal of making the behavior
consistent with userland functions, where null is never accepted
for non-nullable arguments.

This change is expected to cause quite a lot of fallout. In most
cases, calling code should be adjusted to avoid passing null. In
some cases, PHP should be adjusted to make some function arguments
nullable. I have already fixed a number of functions before landing
this, but feel free to file a bug if you encounter a function that
doesn't accept null, but probably should. (The rule of thumb for
this to be applicable is that the function must have special behavior
for 0 or "", which is distinct from the natural behavior of the
parameter.)

RFC: https://wiki.php.net/rfc/deprecate_null_to_scalar_internal_arg

Closes GH-6475.

11 files changed, 22 insertions, 26 deletions

diff --git a/ext/spl/tests/SplFixedArray__construct_param_null.phpt b/ext/spl/tests/SplFixedArray__construct_param_null.phpt
index 919c72021a..acd9d44af5 100644
--- a/ext/spl/tests/SplFixedArray__construct_param_null.phpt
+++ b/ext/spl/tests/SplFixedArray__construct_param_null.phpt
@@ -10,7 +10,8 @@ $array = new SplFixedArray( NULL );
 print_r( $array );
 
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: SplFixedArray::__construct(): Passing null to parameter #1 ($size) of type int is deprecated in %s on line %d
 SplFixedArray Object
 (
 )
diff --git a/ext/spl/tests/SplFixedArray_setSize_param_null.phpt b/ext/spl/tests/SplFixedArray_setSize_param_null.phpt
index ddb37be9f0..dd98935f2f 100644
--- a/ext/spl/tests/SplFixedArray_setSize_param_null.phpt
+++ b/ext/spl/tests/SplFixedArray_setSize_param_null.phpt
@@ -8,6 +8,7 @@ $fixed_array = new SplFixedArray(2);
 $fixed_array->setSize(null);
 var_dump($fixed_array);
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: SplFixedArray::setSize(): Passing null to parameter #1 ($size) of type int is deprecated in %s on line %d
 object(SplFixedArray)#1 (0) {
 }
diff --git a/ext/spl/tests/SplObjectStorage_unserialize_invalid_parameter3.phpt b/ext/spl/tests/SplObjectStorage_unserialize_invalid_parameter3.phpt
index bc9f78a1ca..6934c3af1b 100644
--- a/ext/spl/tests/SplObjectStorage_unserialize_invalid_parameter3.phpt
+++ b/ext/spl/tests/SplObjectStorage_unserialize_invalid_parameter3.phpt
@@ -1,5 +1,5 @@
 --TEST--
-Check that SplObjectStorage::unserialize doesn't throws exception when NULL passed
+Check that SplObjectStorage::unserialize doesn't throws exception when empty string passed
 --CREDITS--
 PHPNW Testfest 2009 - Simon Westcott (swestcott@gmail.com)
 --FILE--
@@ -8,7 +8,7 @@ PHPNW Testfest 2009 - Simon Westcott (swestcott@gmail.com)
 $s = new SplObjectStorage();
 
 try {
-    $s->unserialize(NULL);
+    $s->unserialize('');
 } catch(UnexpectedValueException $e) {
     echo $e->getMessage();
 }
diff --git a/ext/spl/tests/bug46051.phpt b/ext/spl/tests/bug46051.phpt
index cebe8a52d7..535dd2ddae 100644
--- a/ext/spl/tests/bug46051.phpt
+++ b/ext/spl/tests/bug46051.phpt
@@ -6,7 +6,7 @@ Bug #46051 (SplFileInfo::openFile - memory overlap)
 $x = new splfileinfo(__FILE__);
 
 try {
-    $x->openFile(NULL, NULL, []);
+    $x->openFile("", false, []);
 } catch (TypeError $e) { }
 
 var_dump($x->getPathName());
diff --git a/ext/spl/tests/bug61527.phpt b/ext/spl/tests/bug61527.phpt
index fa8291228c..f068897246 100644
--- a/ext/spl/tests/bug61527.phpt
+++ b/ext/spl/tests/bug61527.phpt
@@ -42,12 +42,12 @@ var_dump($ai2->next());
 var_dump($ai2->key());
 
 /* testing RecursiveArrayIterator */
-$ao3 = new ArrayObject(array(), NULL, 'RecursiveArrayIterator');
+$ao3 = new ArrayObject(array(), 0, 'RecursiveArrayIterator');
 $ai3 = $ao3->getIterator();
 
 var_dump($ai3->getChildren());
 
-$ao4 = new ArrayObject(array(1, 2), NULL, 'RecursiveArrayIterator');
+$ao4 = new ArrayObject(array(1, 2), 0, 'RecursiveArrayIterator');
 $ai4 = $ao4->getIterator();
 
 $ai4->next();
diff --git a/ext/spl/tests/bug65387.phpt b/ext/spl/tests/bug65387.phpt
index a5b028954c..e5d501ccf1 100644
--- a/ext/spl/tests/bug65387.phpt
+++ b/ext/spl/tests/bug65387.phpt
@@ -31,13 +31,13 @@ $it2 = new RecursiveCallbackFilterIterator($it, function($elem) use(&$it2) {
 // Cache
 $it = new ArrayIterator();
 $it2 = new CachingIterator($it, CachingIterator::FULL_CACHE);
-$it2[] = $it2;
+$it2['x'] = $it2;
 $it2->next();
 
 // Recursive cache
 $it = new RecursiveArrayIterator();
 $it2 = new RecursiveCachingIterator($it, CachingIterator::FULL_CACHE);
-$it2[] = $it2;
+$it2['x'] = $it2;
 $it2->next();
 
 // Append
diff --git a/ext/spl/tests/bug75717.phpt b/ext/spl/tests/bug75717.phpt
index 77226e1099..920dda9c53 100644
--- a/ext/spl/tests/bug75717.phpt
+++ b/ext/spl/tests/bug75717.phpt
@@ -8,7 +8,7 @@ function flatten(array $nestedArraysAndStrings){
     $iter = new RecursiveIteratorIterator(
         new RecursiveArrayIterator($nestedArraysAndStrings));
     foreach($iter as $leaf){ $flat[] = $leaf; }
-    return join(null, $flat);
+    return join('', $flat);
 }
 
 $noRefs = [[[['some']]],[' nested '],"items"];
diff --git a/ext/spl/tests/fixedarray_011.phpt b/ext/spl/tests/fixedarray_011.phpt
deleted file mode 100644
index eddf320fcc..0000000000
--- a/ext/spl/tests/fixedarray_011.phpt
+++ /dev/null
@@ -1,14 +0,0 @@
---TEST--
-SPL: FixedArray: Testing setSize() with NULL
---FILE--
-<?php
-
-$a = new SplFixedArray(100);
-
-$a->setSize(NULL);
-
-print "ok\n";
-
-?>
---EXPECT--
-ok
diff --git a/ext/spl/tests/fixedarray_014.phpt b/ext/spl/tests/fixedarray_014.phpt
index a6f2fc188c..75108b5868 100644
--- a/ext/spl/tests/fixedarray_014.phpt
+++ b/ext/spl/tests/fixedarray_014.phpt
@@ -4,7 +4,7 @@ SPL: FixedArray: Trying to access inexistent item
 <?php
 
 try {
-    $a = new SplFixedArray(NULL);
+    $a = new SplFixedArray(0);
     echo $a[0]++;
 } catch (Exception $e) {
     echo $e->getMessage();
diff --git a/ext/spl/tests/iterator_044.phpt b/ext/spl/tests/iterator_044.phpt
index 66f722af9a..74321194e0 100644
--- a/ext/spl/tests/iterator_044.phpt
+++ b/ext/spl/tests/iterator_044.phpt
@@ -94,8 +94,12 @@ Warning: Undefined array key "foo" in %s on line %d
 NULL
 ===3===
 NULL
+
+Deprecated: CachingIterator::offsetExists(): Passing null to parameter #1 ($key) of type string is deprecated in %s on line %d
 bool(false)
 
+Deprecated: CachingIterator::offsetGet(): Passing null to parameter #1 ($key) of type string is deprecated in %s on line %d
+
 Warning: Undefined array key "" in %s on line %d
 NULL
 ===4===
@@ -133,8 +137,12 @@ bool(true)
 int(1)
 ===3===
 NULL
+
+Deprecated: CachingIterator::offsetExists(): Passing null to parameter #1 ($key) of type string is deprecated in %s on line %d
 bool(false)
 
+Deprecated: CachingIterator::offsetGet(): Passing null to parameter #1 ($key) of type string is deprecated in %s on line %d
+
 Warning: Undefined array key "" in %s on line %d
 NULL
 ===4===
diff --git a/ext/spl/tests/regexIterator_flags_basic.phpt b/ext/spl/tests/regexIterator_flags_basic.phpt
index 535be00035..d5b778f86b 100644
--- a/ext/spl/tests/regexIterator_flags_basic.phpt
+++ b/ext/spl/tests/regexIterator_flags_basic.phpt
@@ -7,7 +7,7 @@ Felix De Vliegher <felix.devliegher@gmail.com>
 
 $array = array('foo', 'bar', 'baz');
 $iterator = new ArrayIterator($array);
-$regexIterator = new RegexIterator($iterator, "/f/", null, RegexIterator::USE_KEY);
+$regexIterator = new RegexIterator($iterator, "/f/", RegexIterator::MATCH, RegexIterator::USE_KEY);
 
 var_dump($regexIterator->getFlags() === RegexIterator::USE_KEY);