From dcdf22dac38b1650d4347c397e2d78f6e6eb2390 Mon Sep 17 00:00:00 2001
From: Henrik Jess Nielsen <henrik@i80.dk>
Date: Fri, 14 Aug 2026 17:44:11 +0200
Subject: [PATCH] fix(bicep): stop corrupting
 hover/definition/references/symbols/formatting/codeAction with completion
 injections
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_ls_to_client called _inject_completions() on EVERY response with an id+result,
not just textDocument/completion responses. pop_context() defaulted to
{'type': 'unknown'} for any untracked id, which _inject_completions treats as
'inject module-name completions' — so list-shaped LS responses for
definition/references/documentSymbol/formatting/codeAction were silently
replaced or prefixed with the Bicep module catalog list instead of returning
real Bicep LangServer results.

Found via a full LSP-capability audit against production: definition,
references, documentSymbol, formatting and codeAction all incorrectly
returned module-completion items instead of real results.

Fix: pop_context() now returns None when the response id wasn't recorded as
a pending completion request, and _ls_to_client only calls
_inject_completions() when a real completion context was found — every other
response now passes through untouched.
---
 ilsp/bicep_lsp/proxy.py | 16 ++++++++++++----
 tests/test_proxy.py     |  5 +++--
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/ilsp/bicep_lsp/proxy.py b/ilsp/bicep_lsp/proxy.py
index c618dc8..04555e8 100644
--- a/ilsp/bicep_lsp/proxy.py
+++ b/ilsp/bicep_lsp/proxy.py
@@ -187,8 +187,12 @@ class _ProxySession:
 
         return {"type": "unknown"}
 
-    def pop_context(self, msg_id) -> dict:
-        return self.pending.pop(msg_id, {"type": "unknown"})
+    def pop_context(self, msg_id) -> dict | None:
+        """Return the tracked completion context for msg_id, or None if this
+        response id does not correspond to a textDocument/completion request
+        we recorded (e.g. hover/definition/references/... responses must never
+        be treated as completion responses)."""
+        return self.pending.pop(msg_id, None)
 
 
 # ── Completion injection ───────────────────────────────────────────────────────
@@ -316,10 +320,14 @@ def _ls_to_client(
             logger.debug("LS→Client: %d bytes", len(body))
             try:
                 msg = json.loads(body)
-                context: dict = {}
+                context = None
                 if "id" in msg and "result" in msg:
                     context = session.pop_context(msg["id"])
-                out = _inject_completions(msg, context)
+                # Only rewrite responses that actually correspond to a
+                # textDocument/completion request we tracked — any other
+                # response (hover, definition, references, documentSymbol,
+                # formatting, codeAction, ...) must pass through untouched.
+                out = _inject_completions(msg, context) if context is not None else body
             except json.JSONDecodeError:
                 out = body
             conn.sendall(_frame(out))
diff --git a/tests/test_proxy.py b/tests/test_proxy.py
index 091bde8..e03f81f 100644
--- a/tests/test_proxy.py
+++ b/tests/test_proxy.py
@@ -502,6 +502,7 @@ def test_session_records_and_pops_context():
     assert ctx["type"] == "param"
     assert ctx["module"] == "appservice"
 
-    # Second pop returns unknown
-    assert session.pop_context(42)["type"] == "unknown"
+    # Second pop (or any untracked id) returns None — the response must pass
+    # through untouched rather than being mistaken for a completion response.
+    assert session.pop_context(42) is None