Add test that checks ALS initial memory footprint

For eng/ide/ada_language_server#1596

Author: AnthonyLeonardoGracio

testsuite/ada_lsp/initial_memory_footprint/main.adb

@@ -0,0 +1,6 @@
+with Ada.Text_IO;
+
+procedure main is
+begin
+   Ada.Text_IO.Put_Line ("Hello Ada World!");
+end main;

testsuite/ada_lsp/initial_memory_footprint/p.gpr

@@ -0,0 +1,2 @@
+project p is
+end p;

testsuite/ada_lsp/initial_memory_footprint/test.py

@@ -0,0 +1,68 @@
+"""
+Test that ALS initial memory footprint does not exceed a
+given amount of memory when runtime indexing is
+disabled.
+"""
+
+from drivers.pylsp import (
+    ALSLanguageClient,
+    ALSClientServerConfig,
+    test,
+    get_ALS_memory_footprint,
+)
+import os
+
+
+async def check_memory_footprint(
+    lsp: ALSLanguageClient,
+    footprint_lower_bound,
+    footprint_upper_bound,
+):
+    """
+    This checks that the ALS memory footprint is within the given bounds.
+    The bounds should be expresed in MB.
+    """
+    # Send a didOpen for main.adb
+    lsp.didOpenFile("main.adb")
+
+    # Wait for indexing
+    await lsp.awaitIndexingEnd()
+
+    # Check the memory footprint in MB (psutil returns memory info in Bytes): verify
+    # that the initial footprint is within expected bounds
+    mem_footprint = get_ALS_memory_footprint()
+
+    assert footprint_lower_bound < mem_footprint < footprint_upper_bound, (
+        f"Initial memory footprint should be between {footprint_lower_bound}MB "
+        + f"and {footprint_upper_bound}MB. Actual memory is: {mem_footprint}MB"
+    )
+
+
+@test(
+    config=ALSClientServerConfig(
+        [
+            os.environ.get("ALS", "ada_language_server"),
+            "--tracefile",
+            "./traces_with_runtime_indexing.cfg",
+        ]
+    )
+)
+async def test_with_indexing(lsp: ALSLanguageClient) -> None:
+    await check_memory_footprint(
+        lsp, footprint_lower_bound=600, footprint_upper_bound=650
+    )
+
+
+@test(
+    config=ALSClientServerConfig(
+        [
+            os.environ.get("ALS", "ada_language_server"),
+            "--tracefile",
+            "./traces_without_runtime_indexing.cfg",
+        ]
+    )
+)
+async def test_without_indexing(lsp: ALSLanguageClient) -> None:
+    await check_memory_footprint(
+        lsp, footprint_lower_bound=70, footprint_upper_bound=150
+    )

testsuite/ada_lsp/initial_memory_footprint/test.yaml

@@ -0,0 +1,2 @@
+# If the title is the same as the directory name, it can be ommited.
+driver: pylsp

testsuite/ada_lsp/initial_memory_footprint/traces_with_runtime_indexing.cfg

@@ -0,0 +1,27 @@
+# Custom traces file that enables runtime indexing
+# to check initial memory footprint.
+
+>ada_ls_log.$T.$$.log:buffer_size=0:buffer_size=0
+
+# Main trace
+ALS.MAIN=yes
+
+# Full logs, helpful for debugging
+ALS.IN=yes
+ALS.OUT=yes
+
+# Enable runtime indexing for this test
+ALS.RUNTIME_INDEXING=yes
+
+# Testing should include incremental text changes
+#ALS.ALLOW_INCREMENTAL_TEXT_CHANGES=yes > inout.txt:buffer_size=0
+ALS.ALLOW_INCREMENTAL_TEXT_CHANGES=yes
+
+# Activate navigation warnings in test mode
+ALS.NOTIFICATIONS_FOR_IMPRECISE_NAVIGATION=yes
+
+# Disable advanced PP formatting of snippet for most tests
+ALS.COMPLETION.FORMATTING=no
+
+# Disable logging in LSP formatting module
+ALS.FORMATTING=no

testsuite/ada_lsp/initial_memory_footprint/traces_without_runtime_indexing.cfg

@@ -0,0 +1,26 @@
+# Custom traces file that disables runtime indexing
+# to check initial memory footprint.
+
+>ada_ls_log.$T.$$.log:buffer_size=0:buffer_size=0
+
+# Main trace
+ALS.MAIN=yes
+
+# Full logs, helpful for debugging
+ALS.IN=yes
+ALS.OUT=yes
+
+# Disable runtime indexing for this test
+ALS.RUNTIME_INDEXING=no
+
+# Testing should include incremental text changes
+#ALS.ALLOW_INCREMENTAL_TEXT_CHANGES=yes > inout.txt:buffer_size=0
+ALS.ALLOW_INCREMENTAL_TEXT_CHANGES=yes
+
+# Activate navigation warnings in test mode
+ALS.NOTIFICATIONS_FOR_IMPRECISE_NAVIGATION=yes
+# Disable advanced PP formatting of snippet for most tests
+ALS.COMPLETION.FORMATTING=no
+
+# Disable logging in LSP formatting module
+ALS.FORMATTING=no

testsuite/drivers/pylsp.py

@@ -6,6 +6,7 @@
 import json
 import logging
 import os
+import psutil
 import shlex
 import sys
 import urllib
@@ -845,6 +846,19 @@ def URI(src_path: Path | str) -> str:
     return src_uri
 
 
+def find_ALS_process():
+    """
+    Return the ALS process launched by the pyslsp test driver.
+    """
+    for x in psutil.pids():
+        try:
+            p = psutil.Process(x)
+            if p.ppid() == os.getpid() and p.name().startswith("ada_language_server"):
+                return p
+        except psutil.NoSuchProcess:
+            pass
+
+
 def assertEqual(actual: Any, expected: Any) -> None:
     """Raise an AssertionError if actual != expected."""
     if actual != expected:
@@ -878,6 +892,20 @@ def to_str(item: tuple[str, int]):
     )
 
 
+def get_ALS_memory_footprint():
+    """
+    Return the memory footprint in MB of the ALS process launched
+    by the pyslsp test driver.
+    """
+    for x in psutil.pids():
+        try:
+            p = psutil.Process(x)
+            if p.ppid() == os.getpid() and p.name().startswith("ada_language_server"):
+                return p.memory_full_info().rss / (1024**2)
+        except psutil.NoSuchProcess:
+            pass
+
+
 class TestInfraError(Exception):
 
     def __init__(