From 1d0ddfac5d6abed8c13bc9c9c05c9a1066126155 Mon Sep 17 00:00:00 2001
From: Jonathan Swoboda <154711427+swoboda1337@users.noreply.github.com>
Date: Tue, 19 May 2026 12:57:18 -0400
Subject: [PATCH] [espidf] Print RAM summary on ESP32-S3 / unified-DIRAM
 variants (#16494)

---
 esphome/espidf/size_summary.py        |   7 +-
 tests/unit_tests/test_size_summary.py | 128 ++++++++++++++++++++++++++
 2 files changed, 132 insertions(+), 3 deletions(-)
 create mode 100644 tests/unit_tests/test_size_summary.py

diff --git a/esphome/espidf/size_summary.py b/esphome/espidf/size_summary.py
index 9477e664b3..3ba0bf3b4d 100644
--- a/esphome/espidf/size_summary.py
+++ b/esphome/espidf/size_summary.py
@@ -94,9 +94,10 @@ def print_summary(size_json: Path, partitions_csv: Path | None) -> None:
         _LOGGER.debug("Skipping size summary: %s", e)
         return
 
-    dram = data.get("memory_types", {}).get("DRAM") or {}
-    ram_used = dram.get("used")
-    ram_total = dram.get("size")
+    memory_types = data.get("memory_types", {})
+    ram_region = memory_types.get("DRAM") or memory_types.get("DIRAM") or {}
+    ram_used = ram_region.get("used")
+    ram_total = ram_region.get("size")
     if ram_total and ram_used is not None:
         print(f"RAM:   {_format_bar(ram_used, ram_total)}")
 
diff --git a/tests/unit_tests/test_size_summary.py b/tests/unit_tests/test_size_summary.py
new file mode 100644
index 0000000000..933be88476
--- /dev/null
+++ b/tests/unit_tests/test_size_summary.py
@@ -0,0 +1,128 @@
+"""Tests for esphome.espidf.size_summary.print_summary."""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import pytest
+
+from esphome.espidf.size_summary import print_summary
+
+
+def _write_size_json(tmp_path: Path, data: dict) -> Path:
+    """Drop a fake esp_idf_size.json under ``tmp_path`` and return the path."""
+    out = tmp_path / "esp_idf_size.json"
+    out.write_text(json.dumps(data))
+    return out
+
+
+def _esp32_size_data() -> dict:
+    """Synthetic esp_idf_size.json for the original ESP32 (split IRAM/DRAM)."""
+    return {
+        "image_size": 827455,
+        "memory_types": {
+            "DRAM": {
+                "size": 180736,
+                "used": 47332,
+                "sections": {
+                    ".dram0.bss": {"abbrev_name": ".bss", "size": 30616},
+                    ".dram0.data": {"abbrev_name": ".data", "size": 16716},
+                },
+            },
+            "IRAM": {
+                "size": 131072,
+                "used": 80351,
+                "sections": {
+                    ".iram0.text": {"abbrev_name": ".text", "size": 79323},
+                    ".iram0.vectors": {"abbrev_name": ".vectors", "size": 1028},
+                },
+            },
+        },
+    }
+
+
+def _s3_size_data() -> dict:
+    """Synthetic esp_idf_size.json for ESP32-S3 (unified DIRAM)."""
+    return {
+        "image_size": 724215,
+        "memory_types": {
+            "DIRAM": {
+                "size": 341760,
+                "used": 104999,
+                "sections": {
+                    ".iram0.text": {"abbrev_name": ".text", "size": 58051},
+                    ".dram0.bss": {"abbrev_name": ".bss", "size": 27088},
+                    ".dram0.data": {"abbrev_name": ".data", "size": 19708},
+                    ".noinit": {"abbrev_name": ".noinit", "size": 152},
+                },
+            },
+            "IRAM": {
+                "size": 16384,
+                "used": 16384,
+                "sections": {
+                    ".iram0.text": {"abbrev_name": ".text", "size": 15356},
+                    ".iram0.vectors": {"abbrev_name": ".vectors", "size": 1028},
+                },
+            },
+        },
+    }
+
+
+def test_print_summary_esp32_uses_dram(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    """Original ESP32: DRAM has no ``.text``, so RAM = DRAM.used / DRAM.size unchanged."""
+    size_json = _write_size_json(tmp_path, _esp32_size_data())
+    print_summary(size_json, partitions_csv=None)
+    out = capsys.readouterr().out
+    assert "RAM:" in out
+    assert "used 47332 bytes from 180736 bytes" in out
+
+
+def test_print_summary_s3_falls_back_to_diram(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    """ESP32-S3 with no DRAM key falls back to DIRAM and reports raw region usage."""
+    size_json = _write_size_json(tmp_path, _s3_size_data())
+    print_summary(size_json, partitions_csv=None)
+    out = capsys.readouterr().out
+    assert "used 104999 bytes from 341760 bytes" in out
+
+
+def test_print_summary_skips_when_diram_total_collapses(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    """A zero-size region drops the RAM line rather than divide by zero."""
+    size_json = _write_size_json(
+        tmp_path,
+        {
+            "memory_types": {
+                "DIRAM": {
+                    "size": 0,
+                    "used": 0,
+                    "sections": {},
+                },
+            },
+        },
+    )
+    print_summary(size_json, partitions_csv=None)
+    out = capsys.readouterr().out
+    assert "RAM:" not in out
+
+
+def test_print_summary_handles_missing_json(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    """Missing size json is non-fatal and prints nothing."""
+    print_summary(tmp_path / "does_not_exist.json", partitions_csv=None)
+    assert capsys.readouterr().out == ""
+
+
+def test_print_summary_handles_no_memory_types(
+    tmp_path: Path, capsys: pytest.CaptureFixture[str]
+) -> None:
+    """A size json without ``memory_types`` still doesn't crash."""
+    size_json = _write_size_json(tmp_path, {"image_size": 0})
+    print_summary(size_json, partitions_csv=None)
+    assert capsys.readouterr().out == ""