From 91c6ffcf98eec762acd3b61133871b97df3c9a88 Mon Sep 17 00:00:00 2001
From: Tim O'Hare <timohare@gmail.com>
Date: Tue, 18 Aug 2026 22:07:25 +1000
Subject: [PATCH] Fix PDF.close() closing the wrong Page instances (memory
 leak)

close() called flush_cache() -- which clears the cached `_pages` list --
before iterating `self.pages` to close each page. With `_pages` gone, that
iteration re-triggers the `pages` property's parsing branch, producing a
fresh, never-otherwise-referenced set of Page objects, and closes *those*
instead of the ones the caller actually used (e.g. via
`for page in pdf.pages: page.extract_text()`).

The real pages' per-page caches (`_objects`, `_layout`, and the
`get_textmap` lru_cache) are therefore never released by close(), so a
long-lived process that opens many PDFs sequentially sees memory grow
roughly unbounded rather than being freed after each `with pdfplumber.open(...)`
block exits. Three independent reports of this same symptom: #1339, #1229,
#1189.

Fix: close the pages before flushing the cache that they're read from, so
close() operates on the actual pages instead of a discarded reparse.

Added a regression test (test_issue_1339) that fails against the old
ordering and passes with the fix -- confirmed both directions locally.
---
 CHANGELOG.md         |  1 +
 README.md            |  1 +
 pdfplumber/pdf.py    |  9 +++++++--
 tests/test_issues.py | 23 +++++++++++++++++++++++
 4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f9d161e9..314eb190 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ All notable changes to this project will be documented in this file. The format
 ## [Unreleased]
 
 ### Fixed
+- Fix `PDF.close()` closing the wrong `Page` instances: it called `flush_cache()` (which clears the cached `_pages` list) before iterating `self.pages`, so that iteration re-parsed and closed a fresh, never-otherwise-referenced set of pages instead of the ones the caller actually used — leaving the real pages' `_objects`/`_layout`/`get_textmap` caches unreleased. This caused unbounded-seeming memory growth in long-lived processes that open many PDFs sequentially. ([#1339](https://github.com/jsvine/pdfplumber/issues/1339), related: [#1229](https://github.com/jsvine/pdfplumber/issues/1229), [#1189](https://github.com/jsvine/pdfplumber/issues/1189))
 - Initialize PDFium's form environment in `get_page_image` so that filled AcroForm field content is included when rendering pages via `Page.to_image()`. ([#1367](https://github.com/jsvine/pdfplumber/issues/1367))
 - Fix `make venv`, which created the virtual environment at `venv/` but then installed into `${VENV}` (default `.venv/`), causing the target to fail on a fresh checkout (h/t @soodoku). ([ec96f72](https://github.com/jsvine/pdfplumber/commit/ec96f72))
 - Include the wrapped exception's class name in `PdfminerException`'s message when `pdfminer.six` raises an exception without one (e.g. `PDFPasswordIncorrect`), which previously surfaced as a blank error message.
diff --git a/README.md b/README.md
index dc23ac9c..b0638350 100644
--- a/README.md
+++ b/README.md
@@ -577,6 +577,7 @@ Many thanks to the following users who've contributed ideas, features, and fixes
 - [Sebastian Cao](https://github.com/cycsmail)
 - [Kaspar Naraghi](https://github.com/kaninaba94)
 - [Siddharth Gaur](https://github.com/siddharthgaur1)
+- [Timothy O'Hare](https://github.com/timothyohare)
 
 ## Contributing
 
diff --git a/pdfplumber/pdf.py b/pdfplumber/pdf.py
index f3d2dc69..3628c72d 100644
--- a/pdfplumber/pdf.py
+++ b/pdfplumber/pdf.py
@@ -122,11 +122,16 @@ def open(
             raise
 
     def close(self) -> None:
-        self.flush_cache()
-
+        # Must close the pages *before* flush_cache() clears `_pages`; the
+        # `pages` property re-parses (and returns a fresh, never-otherwise-
+        # referenced set of pages) if `_pages` is missing, so flushing first
+        # means the pages actually used by the caller never get their heavy
+        # caches (`_objects`, `_layout`, `get_textmap`) released. See #1339.
         for page in self.pages:
             page.close()
 
+        self.flush_cache()
+
         if not self.stream_is_external:
             self.stream.close()
 
diff --git a/tests/test_issues.py b/tests/test_issues.py
index e0823f2b..ae8c7f31 100644
--- a/tests/test_issues.py
+++ b/tests/test_issues.py
@@ -338,3 +338,26 @@ def test_pr_1195(self):
         ):
             for _ in pdf.annots:
                 pass
+
+    def test_issue_1339(self):
+        """
+        PDF.close() closed the wrong Page instances: flush_cache() ran
+        first and deleted the cached `_pages` list, so the subsequent
+        `for page in self.pages: page.close()` re-parsed and closed a
+        fresh, never-otherwise-referenced set of pages instead of the ones
+        the caller actually used -- leaving the real pages' `_objects` /
+        `_layout` / `get_textmap` caches unreleased after close().
+        https://github.com/jsvine/pdfplumber/issues/1339
+        """
+        path = os.path.join(HERE, "pdfs/issue-33-lorem-ipsum.pdf")
+        pdf = pdfplumber.open(path)
+        pages = pdf.pages
+        for page in pages:
+            page.extract_text()
+            assert hasattr(page, "_objects")
+
+        pdf.close()
+
+        for page in pages:
+            assert not hasattr(page, "_objects")
+            assert page.get_textmap.cache_info().currsize == 0