patch 8.2.2617: Vim9: script variable in block not found by function

Problem:    Vim9: script variable in a block scope not found by a nested
            function.
Solution:   Copy the block scope IDs before compiling the function.

src/testdir/test_vim9_disassemble.vim

@@ -947,7 +947,7 @@ def NestedOuter()
   enddef
 enddef
 
-def Test_nested_func()
+def Test_disassemble_nested_func()
    var instr = execute('disassemble NestedOuter')
    assert_match('NestedOuter\_s*' ..
         'def g:Inner()\_s*' ..
@@ -965,7 +965,7 @@ def NestedDefList()
   def /Info/
 enddef
 
-def Test_nested_def_list()
+def Test_disassemble_nested_def_list()
    var instr = execute('disassemble NestedDefList')
    assert_match('NestedDefList\_s*' ..
         'def\_s*' ..

src/testdir/test_vim9_func.vim

@@ -393,7 +393,6 @@ def Test_nested_function()
   CheckDefFailure(lines, 'E1117:')
 
   # nested function inside conditional
-  # TODO: should it work when "thecount" is inside the "if"?
   lines =<< trim END
       vim9script
       var thecount = 0
@@ -411,6 +410,25 @@ def Test_nested_function()
       assert_equal(2, Test())
   END
   CheckScriptSuccess(lines)
+
+  # also works when "thecount" is inside the "if" block
+  lines =<< trim END
+      vim9script
+      if true
+        var thecount = 0
+        def Test(): number
+          def TheFunc(): number
+            thecount += 1
+            return thecount
+          enddef
+          return TheFunc()
+        enddef
+      endif
+      defcompile
+      assert_equal(1, Test())
+      assert_equal(2, Test())
+  END
+  CheckScriptSuccess(lines)
 enddef
 
 def Test_not_nested_function()

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2617,
 /**/
     2616,
 /**/

src/vim9compile.c

@@ -5183,6 +5183,21 @@ compile_nested_function(exarg_T *eap, cctx_T *cctx)
 	r = eap->skip ? OK : FAIL;
 	goto theend;
     }
+
+    // copy over the block scope IDs before compiling
+    if (!is_global && cctx->ctx_ufunc->uf_block_depth > 0)
+    {
+	int block_depth = cctx->ctx_ufunc->uf_block_depth;
+
+	ufunc->uf_block_ids = ALLOC_MULT(int, block_depth);
+	if (ufunc->uf_block_ids != NULL)
+	{
+	    mch_memmove(ufunc->uf_block_ids, cctx->ctx_ufunc->uf_block_ids,
+						    sizeof(int) * block_depth);
+	    ufunc->uf_block_depth = block_depth;
+	}
+    }
+
     if (func_needs_compiling(ufunc, PROFILING(ufunc))
 	    && compile_def_function(ufunc, TRUE, PROFILING(ufunc), cctx)
 								       == FAIL)
@@ -5209,25 +5224,12 @@ compile_nested_function(exarg_T *eap, cctx_T *cctx)
 	// Define a local variable for the function reference.
 	lvar_T	*lvar = reserve_local(cctx, name_start, name_end - name_start,
 						    TRUE, ufunc->uf_func_type);
-	int block_depth = cctx->ctx_ufunc->uf_block_depth;
 
 	if (lvar == NULL)
 	    goto theend;
 	if (generate_FUNCREF(cctx, ufunc) == FAIL)
 	    goto theend;
 	r = generate_STORE(cctx, ISN_STORE, lvar->lv_idx, NULL);
-
-	// copy over the block scope IDs
-	if (block_depth > 0)
-	{
-	    ufunc->uf_block_ids = ALLOC_MULT(int, block_depth);
-	    if (ufunc->uf_block_ids != NULL)
-	    {
-		mch_memmove(ufunc->uf_block_ids, cctx->ctx_ufunc->uf_block_ids,
-						    sizeof(int) * block_depth);
-		ufunc->uf_block_depth = block_depth;
-	    }
-	}
     }
     // TODO: warning for trailing text?