vim-patch:8.1.1585: :let-heredoc does not trim enough

Problem:    :let-heredoc does not trim enough.
Solution:   Trim indent from the contents based on the indent of the first
            line.  Use let-heredoc in more tests.
https://github.com/vim/vim/commit/e7eb92708ec2092a2fc11e78703b5dcf83844412

1 files changed, 38 insertions, 14 deletions

diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index a899dbcd3a..bedfe2d6d0 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -1521,7 +1521,9 @@ heredoc_get(exarg_T *eap, char_u *cmd)
 {
   char_u *marker;
   char_u *p;
-  int indent_len = 0;
+  int marker_indent_len = 0;
+  int text_indent_len = 0;
+  char_u *text_indent = NULL;
 
   if (eap->getline == NULL) {
     EMSG(_("E991: cannot use =<< here"));
@@ -1534,14 +1536,16 @@ heredoc_get(exarg_T *eap, char_u *cmd)
       && (cmd[4] == NUL || ascii_iswhite(cmd[4]))) {
     cmd = skipwhite(cmd + 4);
 
-    // Trim the indentation from all the lines in the here document
+    // Trim the indentation from all the lines in the here document.
     // The amount of indentation trimmed is the same as the indentation of
-    // the :let command line.
+    // the first line after the :let command line.  To find the end marker
+    // the indent of the :let command line is trimmed.
     p = *eap->cmdlinep;
     while (ascii_iswhite(*p)) {
       p++;
-      indent_len++;
+      marker_indent_len++;
     }
+    text_indent_len = -1;
   }
 
   // The marker is the next word.  Default marker is "."
@@ -1559,28 +1563,48 @@ heredoc_get(exarg_T *eap, char_u *cmd)
 
   list_T *l = tv_list_alloc(0);
   for (;;) {
-    int i = 0;
+    int mi = 0;
+    int ti = 0;
 
     char_u *theline = eap->getline(NUL, eap->cookie, 0, false);
-    if (theline != NULL && indent_len > 0) {
-      // trim the indent matching the first line
-      if (STRNCMP(theline, *eap->cmdlinep, indent_len) == 0) {
-        i = indent_len;
-      }
-    }
-
     if (theline == NULL) {
       EMSG2(_("E990: Missing end marker '%s'"), marker);
       break;
     }
-    if (STRCMP(marker, theline + i) == 0) {
+
+    // with "trim": skip the indent matching the :let line to find the
+    // marker
+    if (marker_indent_len > 0
+        && STRNCMP(theline, *eap->cmdlinep, marker_indent_len) == 0) {
+        mi = marker_indent_len;
+    }
+    if (STRCMP(marker, theline + mi) == 0) {
       xfree(theline);
       break;
     }
+    if (text_indent_len == -1 && *theline != NUL) {
+        // set the text indent from the first line.
+        p = theline;
+        text_indent_len = 0;
+        while (ascii_iswhite(*p)) {
+            p++;
+            text_indent_len++;
+        }
+        text_indent = vim_strnsave(theline, text_indent_len);
+    }
+    // with "trim": skip the indent matching the first line
+    if (text_indent != NULL) {
+        for (ti = 0; ti < text_indent_len; ti++) {
+            if (theline[ti] != text_indent[ti]) {
+                break;
+            }
+        }
+    }
 
-    tv_list_append_string(l, (char *)(theline + i), -1);
+    tv_list_append_string(l, (char *)(theline + ti), -1);
     xfree(theline);
   }
+  xfree(text_indent);
 
   return l;
 }