From 284983657fc3fae835ec52c5ae766d379d090809 Mon Sep 17 00:00:00 2001
From: XeroOl <xerool@protonmail.com>
Date: Fri, 1 Mar 2024 14:51:18 -0600
Subject: [PATCH] continue compilation in broken let statements

---
 src/fennel-ls/compiler.fnl | 14 ++++++++++----
 test/completion.fnl        |  7 +++----
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/src/fennel-ls/compiler.fnl b/src/fennel-ls/compiler.fnl
index d2f1676..e718b15 100644
--- a/src/fennel-ls/compiler.fnl
+++ b/src/fennel-ls/compiler.fnl
@@ -230,14 +230,20 @@ identifiers are declared / referenced in which places."
         (where [sym] (multisym? sym) (: (tostring sym) :find ":"))
         (reference sym scope :read)))
 
-    (λ recoverable? [msg]
+    (λ attempt-to-recover! [msg ?ast]
       (or (= 1 (msg:find "unknown identifier"))
           (= 1 (msg:find "expected closing delimiter"))
           (= 1 (msg:find "expected body expression"))
           (= 1 (msg:find "expected condition and body"))
           (= 1 (msg:find "expected whitespace before opening delimiter"))
           (= 1 (msg:find "malformed multisym"))
-          (= 1 (msg:find "expected at least one pattern/body pair"))))
+          (= 1 (msg:find "expected at least one pattern/body pair"))
+          (when (and (sequence? ?ast)
+                     (= 1 (% (length ?ast ) 2))
+                     (= 1 (msg:find "expected even number of name/value bindings")))
+            (table.insert ?ast (sym :nil))
+            true)))
+
 
     (λ on-compile-error [_ msg ast call-me-to-reset-the-compiler]
       (let [range (or (message.ast->range self file ast)
@@ -248,7 +254,7 @@ identifiers are declared / referenced in which places."
            :severity message.severity.ERROR
            :code 201
            :codeDescription "compiler error"}))
-      (if (recoverable? msg)
+      (if (attempt-to-recover! msg ast)
         true
         (do
           (call-me-to-reset-the-compiler)
@@ -263,7 +269,7 @@ identifiers are declared / referenced in which places."
            :severity message.severity.ERROR
            :code 101
            :codeDescription "parse error"}))
-      (if (recoverable? msg)
+      (if (attempt-to-recover! msg)
         true
         (do
           (call-me-to-reset-the-compiler)
diff --git a/test/completion.fnl b/test/completion.fnl
index 690b017..e2006bd 100644
--- a/test/completion.fnl
+++ b/test/completion.fnl
@@ -88,10 +88,9 @@
               fo|" [:foo :bar] [])
   (check "(local foo 10)
           (local bar (let [y foo] |" [:foo :y] [])
-  ;; TODO add compile check for incomplete let
-  ; (check "(let [foo 10
-  ;               bar 20
-  ;               _ |" [:foo :bar] [])
+  (check "(let [foo 10
+                bar 20
+                _ |" [:foo :bar] [])
   (check "(let [foo 10
                 bar 20
                 _ fo|" [:foo :bar] [])