Merge pull request #9422 from EgorBakulin/#9411/concat-should-never-r…

…emove-non-empty-non-falsy-from-string concat should never remove non empty non falsy from string #9411
vimeo · Feb 27, 2023 · 99b5987 · 99b5987
2 parents 5083e18 + 67d26d3
commit 99b5987
Show file tree

Hide file tree

Showing 2 changed files with 51 additions and 0 deletions.
diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/ConcatAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/ConcatAnalyzer.php
@@ -29,10 +29,12 @@
 use Psalm\Type\Atomic\TFalse;
 use Psalm\Type\Atomic\TFloat;
 use Psalm\Type\Atomic\TInt;
+use Psalm\Type\Atomic\TLiteralString;
 use Psalm\Type\Atomic\TLowercaseString;
 use Psalm\Type\Atomic\TNamedObject;
 use Psalm\Type\Atomic\TNonEmptyNonspecificLiteralString;
 use Psalm\Type\Atomic\TNonEmptyString;
+use Psalm\Type\Atomic\TNonFalsyString;
 use Psalm\Type\Atomic\TNonspecificLiteralString;
 use Psalm\Type\Atomic\TNull;
 use Psalm\Type\Atomic\TNumericString;
@@ -277,6 +279,31 @@ public static function analyze(
                     }
                 }
             }
+        } elseif ($left_type || $right_type) {
+            /**
+             * @var Union $known_operand
+             */
+            $known_operand = $right_type ?? $left_type;
+
+            if ($known_operand->isSingle()) {
+                $known_operands_atomic = $known_operand->getSingleAtomic();
+
+                if ($known_operands_atomic instanceof TNonEmptyString) {
+                    $result_type = Type::getNonEmptyString();
+                }
+
+                if ($known_operands_atomic instanceof TNonFalsyString) {
+                    $result_type = Type::getNonFalsyString();
+                }
+
+                if ($known_operands_atomic instanceof TLiteralString) {
+                    if ($known_operands_atomic->value) {
+                        $result_type = Type::getNonFalsyString();
+                    } elseif ($known_operands_atomic->value !== '') {
+                        $result_type = Type::getNonEmptyString();
+                    }
+                }
+            }
         }
     }
 

diff --git a/tests/BinaryOperationTest.php b/tests/BinaryOperationTest.php
@@ -489,6 +489,30 @@ function foobar(string $bar): string
                     foobar($foo . $bar);
                 ',
             ],
+            'concatenateNonFalsyStringWithUndefinedConstant' => [
+                'code' => '<?php
+                    /**
+                     * @param non-falsy-string $arg
+                     * @return non-falsy-string
+                     */
+                    function foo( $arg ) {
+                        /** @psalm-suppress UndefinedConstant */
+                        return FOO . $arg;
+                    }
+                ',
+            ],
+            'concatenateNonEmptyStringWithUndefinedConstant' => [
+                'code' => '<?php
+                    /**
+                     * @param non-empty-string $arg
+                     * @return non-empty-string
+                     */
+                    function foo( $arg ) {
+                        /** @psalm-suppress UndefinedConstant */
+                        return FOO . $arg;
+                    }
+                ',
+            ],
             'possiblyInvalidAdditionOnBothSides' => [
                 'code' => '<?php
                     function foo(string $s) : int {