# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1673277303 -3600
# Node ID 2f8a3cde553f73e7e822b38229b72c133e2ca02b
# Parent  9e91208332468b6469d87905ec76997c64ce4e49
patch 9.0.1164: evaluating string expression advances function line

Commit: https://github.com/vim/vim/commit/01c5f2addf86b8d8940d71c92f6219f14a6df99e
Author: h-east <h.east.727@gmail.com>
Date:   Mon Jan 9 15:10:40 2023 +0000

    patch 9.0.1164: evaluating string expression advances function line

    Problem:    Evaluating string expression advances function line.
    Solution:   Disable function lines while parsing a string expression.
                (Hirohito Higashi, closes #11796)

diff --git a/src/testdir/test_vim9_expr.vim b/src/testdir/test_vim9_expr.vim
--- a/src/testdir/test_vim9_expr.vim
+++ b/src/testdir/test_vim9_expr.vim
@@ -3700,6 +3700,17 @@ def Test_expr9_method_call_linebreak()
       assert_equal('', v:errmsg)
   END
   v9.CheckScriptSuccess(lines)
+
+  # this was skipping over the expression without an error
+  lines =<< trim END
+      vim9script
+      def Test(s: string): string
+        return substitute(s, 'A', '\=toupper("x")', 'g')
+                          ->tolower()
+      enddef
+      assert_equal('xbcd', Test('ABCD'))
+  END
+  v9.CheckScriptSuccess(lines)
 enddef
 
 def Test_expr9_method_call_import()
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1164,
+/**/
     1163,
 /**/
     1162,
diff --git a/src/vim9expr.c b/src/vim9expr.c
--- a/src/vim9expr.c
+++ b/src/vim9expr.c
@@ -733,7 +733,15 @@ compile_string(isn_T *isn, cctx_T *cctx,
     cctx->ctx_instr.ga_len = 0;
     cctx->ctx_instr.ga_maxlen = 0;
     cctx->ctx_instr.ga_data = NULL;
+
+    // avoid peeking a next line
+    int galen_save = cctx->ctx_ufunc->uf_lines.ga_len;
+    cctx->ctx_ufunc->uf_lines.ga_len = 0;
+
     expr_res = compile_expr0(&s, cctx);
+
+    cctx->ctx_ufunc->uf_lines.ga_len = galen_save;
+
     s = skipwhite(s);
     trailing_error = *s != NUL;