[Str] add after and before helpers

src/Psl/Internal/Loader.php

@@ -215,6 +215,7 @@ final class Loader
         'Psl\Str\Byte\search',
         'Psl\Str\Byte\search_ci',
         'Psl\Str\Byte\search_last',
+        'Psl\Str\Byte\search_last_ci',
         'Psl\Str\Byte\shuffle',
         'Psl\Str\Byte\slice',
         'Psl\Str\Byte\splice',
@@ -229,6 +230,14 @@ final class Loader
         'Psl\Str\Byte\uppercase',
         'Psl\Str\Byte\words',
         'Psl\Str\Byte\wrap',
+        'Psl\Str\Byte\after',
+        'Psl\Str\Byte\after_ci',
+        'Psl\Str\Byte\after_last',
+        'Psl\Str\Byte\after_last_ci',
+        'Psl\Str\Byte\before',
+        'Psl\Str\Byte\before_ci',
+        'Psl\Str\Byte\before_last',
+        'Psl\Str\Byte\before_last_ci',
         'Psl\Str\capitalize',
         'Psl\Str\capitalize_words',
         'Psl\Str\chr',
@@ -278,6 +287,14 @@ final class Loader
         'Psl\Str\uppercase',
         'Psl\Str\width',
         'Psl\Str\wrap',
+        'Psl\Str\after',
+        'Psl\Str\after_ci',
+        'Psl\Str\after_last',
+        'Psl\Str\after_last_ci',
+        'Psl\Str\before',
+        'Psl\Str\before_ci',
+        'Psl\Str\before_last',
+        'Psl\Str\before_last_ci',
         'Psl\invariant',
         'Psl\invariant_violation',
         'Psl\sequence',
@@ -353,6 +370,14 @@ final class Loader
         'Psl\Str\Grapheme\starts_with_ci',
         'Psl\Str\Grapheme\strip_prefix',
         'Psl\Str\Grapheme\strip_suffix',
+        'Psl\Str\Grapheme\after',
+        'Psl\Str\Grapheme\after_ci',
+        'Psl\Str\Grapheme\after_last',
+        'Psl\Str\Grapheme\after_last_ci',
+        'Psl\Str\Grapheme\before',
+        'Psl\Str\Grapheme\before_ci',
+        'Psl\Str\Grapheme\before_last',
+        'Psl\Str\Grapheme\before_last_ci',
     ];
 
     public const INTERFACES = [

src/Psl/Str/Byte/after.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function after(string $haystack, string $needle, int $offset = 0): ?string
+{
+    $offset = search($haystack, $needle, $offset);
+    if (null === $offset) {
+        return null;
+    }
+
+        $offset += length($needle);
+
+    return slice($haystack, $offset, null);
+}

src/Psl/Str/Byte/after_ci.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function after_ci(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $offset = search_ci($haystack, $needle, $offset);
+    if (null === $offset) {
+        return null;
+    }
+
+    $offset += length($needle);
+
+    return slice($haystack, $offset, null);
+}

src/Psl/Str/Byte/after_last.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ * @throws Psl\Exception\InvariantViolationException If an invalid $encoding is provided.
+ *
+ * @psalm-pure
+ */
+function after_last(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $position = search_last($haystack, $needle, $offset);
+    if (null === $position) {
+        return null;
+    }
+
+    $position += length($needle);
+
+    return slice($haystack, $position);
+}

src/Psl/Str/Byte/after_last_ci.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function after_last_ci(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $position = search_last_ci($haystack, $needle, $offset);
+    if (null === $position) {
+        return null;
+    }
+
+    $position += length($needle);
+
+    return slice($haystack, $position);
+}

src/Psl/Str/Byte/before.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function before(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $length = search($haystack, $needle, $offset);
+    if (null === $length) {
+        return null;
+    }
+
+        $length += length($needle);
+
+    return slice($haystack, 0, $length);
+}

src/Psl/Str/Byte/before_ci.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function before_ci(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $length = search_ci($haystack, $needle, $offset);
+    if (null === $length) {
+        return null;
+    }
+
+        $length += length($needle);
+
+    return slice($haystack, 0, $length);
+}

src/Psl/Str/Byte/before_last.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function before_last(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $length = search_last($haystack, $needle, $offset);
+    if (null === $length) {
+        return null;
+    }
+
+        $length += length($needle);
+
+    return slice($haystack, 0, $length);
+}

src/Psl/Str/Byte/before_last_ci.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function before_last_ci(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $length = search_last_ci($haystack, $needle, $offset);
+    if (null === $length) {
+        return null;
+    }
+
+        $length += length($needle);
+
+    return slice($haystack, 0, $length);
+}

src/Psl/Str/Byte/search_last.php

@@ -23,6 +23,10 @@
  */
 function search_last(string $haystack, string $needle, int $offset = 0): ?int
 {
+    if ('' === $needle) {
+        return null;
+    }
+
     $haystack_length = length($haystack);
     Psl\invariant($offset >= -$haystack_length && $offset <= $haystack_length, 'Offset is out-of-bounds.');
 

src/Psl/Str/Byte/search_last_ci.php

@@ -0,0 +1,32 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Byte;
+
+use Psl;
+
+/**
+ * Returns the last position of the 'needle' string in the 'haystack' string,
+ * or null if it isn't found (case-insensitive).
+ *
+ * An optional offset determines where in the haystack (from the beginning) the
+ * search begins. If the offset is negative, the search will begin that many
+ * characters from the end of the string and go backwards. If the offset is
+ * out-of-bounds, an InvariantViolationException will be thrown.
+ *
+ * @psalm-pure
+ *
+ * @throws Psl\Exception\InvariantViolationException If $offset is out-of-bounds.
+ */
+function search_last_ci(string $haystack, string $needle, int $offset = 0): ?int
+{
+    if ('' === $needle) {
+        return null;
+    }
+
+    $haystack_length = length($haystack);
+    Psl\invariant($offset >= -$haystack_length && $offset <= $haystack_length, 'Offset is out-of-bounds.');
+
+    return false === ($pos = strripos($haystack, $needle, $offset)) ? null : $pos;
+}

src/Psl/Str/Grapheme/after.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Grapheme;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function after(string $haystack, string $needle, int $offset = 0): ?string
+{
+    $offset = search($haystack, $needle, $offset);
+    if (null === $offset) {
+        return null;
+    }
+
+        $offset += length($needle);
+
+    return slice($haystack, $offset, null);
+}

src/Psl/Str/Grapheme/after_ci.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Psl\Str\Grapheme;
+
+use Psl;
+
+/**
+ * @throws Psl\Exception\InvariantViolationException If the $offset is out-of-bounds.
+ *
+ * @psalm-pure
+ */
+function after_ci(
+    string $haystack,
+    string $needle,
+    int $offset = 0
+): ?string {
+    $offset = search_ci($haystack, $needle, $offset);
+    if (null === $offset) {
+        return null;
+    }
+
+        $offset += length($needle);
+
+    return slice($haystack, $offset, null);
+}