From 8801edb7a2e4f3bf9bcd9c6444ddbead43b0fbeb Mon Sep 17 00:00:00 2001
From: Nicolas MURE <nicolas.mure@knplabs.com>
Date: Thu, 10 Aug 2017 00:06:53 +0200
Subject: [PATCH] also yield URIs to save memory

---
 src/Index/AbstractAggregateIndex.php | 12 +++++-------
 src/Index/Index.php                  | 15 +++++++++++----
 src/Index/ReadableIndex.php          |  6 +++---
 src/Server/TextDocument.php          | 20 ++++++++++++++++----
 4 files changed, 35 insertions(+), 18 deletions(-)

diff --git a/src/Index/AbstractAggregateIndex.php b/src/Index/AbstractAggregateIndex.php
index a5826ab..7ba3870 100644
--- a/src/Index/AbstractAggregateIndex.php
+++ b/src/Index/AbstractAggregateIndex.php
@@ -160,19 +160,17 @@ abstract class AbstractAggregateIndex implements ReadableIndex
     }
 
     /**
-     * Returns all URIs in this index that reference a symbol
+     * Returns a Generator providing all URIs in this index that reference a symbol
      *
      * @param string $fqn The fully qualified name of the symbol
-     * @return string[]
+     * @return \Generator providing string[]
      */
-    public function getReferenceUris(string $fqn): array
+    public function getReferenceUris(string $fqn): \Generator
     {
-        $refs = [];
         foreach ($this->getIndexes() as $index) {
-            foreach ($index->getReferenceUris($fqn) as $ref) {
-                $refs[] = $ref;
+            foreach ($index->getReferenceUris($fqn) as $uri) {
+                yield $uri;
             }
         }
-        return $refs;
     }
 }
diff --git a/src/Index/Index.php b/src/Index/Index.php
index 9130246..8d8675d 100644
--- a/src/Index/Index.php
+++ b/src/Index/Index.php
@@ -197,14 +197,21 @@ class Index implements ReadableIndex, \Serializable
     }
 
     /**
-     * Returns all URIs in this index that reference a symbol
+     * Returns a Generator providing all URIs in this index that reference a symbol
      *
      * @param string $fqn The fully qualified name of the symbol
-     * @return string[]
+     * @return \Generator providing string[]
      */
-    public function getReferenceUris(string $fqn): array
+    public function getReferenceUris(string $fqn): \Generator
     {
-        return $this->references[$fqn] ?? [];
+        $uris = isset($this->references[$fqn])
+            ? $this->references[$fqn]
+            : []
+        ;
+
+        foreach ($uris as $uri) {
+            yield $uri;
+        }
     }
 
     /**
diff --git a/src/Index/ReadableIndex.php b/src/Index/ReadableIndex.php
index 8d4e1ca..6e2b8c6 100644
--- a/src/Index/ReadableIndex.php
+++ b/src/Index/ReadableIndex.php
@@ -63,10 +63,10 @@ interface ReadableIndex extends EmitterInterface
     public function getDefinition(string $fqn, bool $globalFallback = false);
 
     /**
-     * Returns all URIs in this index that reference a symbol
+     * Returns a Generator providing all URIs in this index that reference a symbol
      *
      * @param string $fqn The fully qualified name of the symbol
-     * @return string[]
+     * @return \Generator providing string[]
      */
-    public function getReferenceUris(string $fqn): array;
+    public function getReferenceUris(string $fqn): \Generator;
 }
diff --git a/src/Server/TextDocument.php b/src/Server/TextDocument.php
index 58e7074..46e822a 100644
--- a/src/Server/TextDocument.php
+++ b/src/Server/TextDocument.php
@@ -219,10 +219,9 @@ class TextDocument
                         return [];
                     }
                 }
-                $refDocuments = yield Promise\all(array_map(
-                    [$this->documentLoader, 'getOrLoad'],
-                    $this->index->getReferenceUris($fqn)
-                ));
+                $refDocuments = yield Promise\all(iterator_to_array(
+                    $this->getOrLoadReferences($fqn))
+                );
                 foreach ($refDocuments as $document) {
                     $refs = $document->getReferenceNodesByFqn($fqn);
                     if ($refs !== null) {
@@ -397,4 +396,17 @@ class TextDocument
             return [new SymbolLocationInformation($descriptor, $def->symbolInformation->location)];
         });
     }
+
+    /**
+     * Gets or loads the documents referencing the given FQN.
+     *
+     * @param string $fqn
+     * @return \Generator providing Promise
+     */
+    private function getOrLoadReferences(string $fqn): \Generator
+    {
+        foreach ($this->index->getReferenceUris($fqn) as $ref) {
+            yield $this->documentLoader->getOrLoad($ref);
+        }
+    }
 }