Additional indentation recovery for newline and case construction.

The newline indentation uses the indentation of the next non-comment
sibling node.  When this node was an ERROR, the catch-all indentation
rule was matched which placed the newline at column 0.  Now, ERROR
nodes are handled by the indentation error recovery logic and newline
indentation prior to an ERROR node will be chosen according to this
logic.

The "end" corresponding to a case construction was not being properly
indented to the same level as the beginning of the case construction,
within the indentation error recovery logic.  This has been corrected.

Additional tests have been added to check indentation error recovery
logic for "end" nodes of a project, package and case construction
declaration.  A test was also added to check for newline indentation
just prior to an ERROR node.

gpr-ts-mode.el

@@ -4,7 +4,7 @@
 
 ;; Author: Troy Brown <[email protected]>
 ;; Created: February 2023
-;; Version: 0.6.4
+;; Version: 0.6.5
 ;; Keywords: gpr gnat ada languages tree-sitter
 ;; URL: https://github.com/brownts/gpr-ts-mode
 ;; Package-Requires: ((emacs "29.1"))
@@ -326,7 +326,11 @@ If OP is nil or \\='anchor\\=', determine recovery anchor.  If OP is
     (let ((compound-alist
            `(("when"    . ( :compound-type "case_item"))
              ("case"    . ( :compound-type "case_construction"
-                            :offset gpr-ts-mode-indent-when-offset))
+                            :offset
+                            (lambda (_anchor)
+                              (if (and ,node (string-equal (treesit-node-type ,node) "end"))
+                                  0
+                                gpr-ts-mode-indent-when-offset))))
              ("package" . ( :compound-type "package_declaration"
                             :offset
                             (lambda (_anchor)
@@ -588,9 +592,10 @@ Return nil if no child of that type is found."
       (gpr-ts-mode--anchor-first-sibling-matching "case_item")
       gpr-ts-mode-indent-offset)
 
-     ;; Parent ERROR recovery rules.
+     ;; Error recovery rules.
 
      ((and (or (parent-is "ERROR")
+               (node-is "ERROR")
                (gpr-ts-mode--prev-sibling-matches-p "ERROR"))
            (gpr-ts-mode--indent-error-recovery-exists-p))
       (gpr-ts-mode--anchor-of-indent-error-recovery)

test/resources/indent-top_down-nl.erts

@@ -389,3 +389,65 @@ project Hello_World is
    for Exec_Dir use Project'Project_Dir;
    |
 =-=-=
+
+Name: Handle next sibling being an ERROR node
+
+=-=
+project Hello_World is
+   package Binder is
+      for Default_Switches ("Ada") use|
+
+   package Compiler is
+      for Default_Switches ("Ada") use ("-g");
+   end Compiler;
+end Hello_World;
+=-=
+project Hello_World is
+   package Binder is
+      for Default_Switches ("Ada") use
+      |
+
+   package Compiler is
+      for Default_Switches ("Ada") use ("-g");
+   end Compiler;
+end Hello_World;
+=-=-=
+
+Name: Anchor "end" to project
+
+=-=
+project Hello_World is
+   end|
+=-=
+project Hello_World is
+end
+   |
+=-=-=
+
+Name: Anchor "end" to package
+
+=-=
+project Hello_World is
+   package Compiler is
+      end|
+=-=
+project Hello_World is
+   package Compiler is
+   end
+      |
+=-=-=
+
+Name: Anchor "end" to case
+
+=-=
+project Hello_World is
+   package Compiler is
+      case Build is
+         end|
+=-=
+project Hello_World is
+   package Compiler is
+      case Build is
+      end
+         |
+=-=-=