Fix indentation with nested dicts

debian/changelog

@@ -1,3 +1,9 @@
+jinjaturtle (0.5.2) unstable; urgency=medium
+
+  * Fix indentation problems with nested dicts
+
+ -- Miguel Jacq <mig@mig5.net>  Fri, 19 Jun 2026 18:33:00 +1000
+
 jinjaturtle (0.5.1) unstable; urgency=medium
 
   * Empty dicts and lists are now emitted as leaf defaults.

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "jinjaturtle"
-version = "0.5.1"
+version = "0.5.2"
 description = "Convert config files into Ansible defaults and Jinja2 templates."
 authors = ["Miguel Jacq <mig@mig5.net>"]
 license = "GPL-3.0-or-later"

rpm/jinjaturtle.spec

@@ -1,4 +1,4 @@
-%global upstream_version 0.5.1
+%global upstream_version 0.5.2
 
 Name:           jinjaturtle
 Version:        %{upstream_version}
@@ -43,6 +43,8 @@ Convert config files into Ansible defaults and Jinja2 templates.
 
 %changelog
 * Fri Jun 19 2026 Miguel Jacq <mig@mig5.net> - %{version}-%{release}
+- Fix indentation problems with nested dicts
+* Fri Jun 19 2026 Miguel Jacq <mig@mig5.net> - %{version}-%{release}
 - Empty dicts and lists are now emitted as leaf defaults.
 * Tue May 11 2026 Miguel Jacq <mig@mig5.net> - %{version}-%{release}
 - Support ssh configs

src/jinjaturtle/handlers/yaml.py

@@ -208,12 +208,21 @@ class YamlHandler(DictLikeHandler):
             stripped = raw_line.lstrip()
             indent = len(raw_line) - len(stripped)
 
-            # If we're skipping lines (inside a loop section), check if we can stop
+            # If we're skipping lines inside a collection replaced by a loop,
+            # continue through YAML's indentless sequence style too, where list
+            # items can appear at the same indentation as the parent key:
+            #
+            #   images:
+            #   - ubuntu
+            #   - debian
+            #
+            # Stop only when a non-list item at the parent indentation appears,
+            # or when indentation moves above the parent collection.
             if skip_until_indent is not None:
-                if (
-                    indent <= skip_until_indent
-                    and stripped
-                    and not stripped.startswith("#")
+                if not stripped or stripped.startswith("#"):
+                    continue
+                if indent < skip_until_indent or (
+                    indent == skip_until_indent and not stripped.startswith("- ")
                 ):
                     skip_until_indent = None
                 else:
@@ -374,39 +383,36 @@ class YamlHandler(DictLikeHandler):
         collection_var = self.make_var_name(role_prefix, candidate.path)
         item_var = candidate.loop_var
 
-        lines = []
-
+        lines: list[str] = []
         if not is_list:
-            # Dict-style: key: {% for ... %}
             key = candidate.path[-1] if candidate.path else "items"
             lines.append(f"{indent_str}{key}:")
-            lines.append(f"{indent_str}  {{% for {item_var} in {collection_var} -%}}")
-        else:
-            # List-style: just the loop
-            lines.append(f"{indent_str}{{% for {item_var} in {collection_var} -%}}")
 
-        # Generate template for item structure
+        item_lines: list[str] = []
         if candidate.items:
             sample_item = candidate.items[0]
             item_indent = indent + 2 if not is_list else indent
+            item_indent_str = " " * item_indent
 
             if candidate.item_schema == "scalar":
-                # Simple list of scalars
-                if is_list:
-                    lines.append(f"{indent_str}- {{{{ {item_var} }}}}")
-                else:
-                    lines.append(f"{indent_str}  - {{{{ {item_var} }}}}")
-
+                item_lines.append(f"{item_indent_str}- {{{{ {item_var} }}}}")
             elif candidate.item_schema in ("simple_dict", "nested"):
-                # List of dicts or complex items - these are ALWAYS list items in YAML
                 item_lines = self._dict_to_yaml_lines(
                     sample_item, item_var, item_indent, is_list_item=True
                 )
-                lines.extend(item_lines)
 
-        # Close loop
-        close_indent = indent + 2 if not is_list else indent
-        lines.append(f"{' ' * close_indent}{{% endfor %}}")
+        if item_lines:
+            # Put the first YAML item on the same physical line as the Jinja
+            # ``for`` tag. With default Jinja whitespace settings this avoids
+            # rendering a blank line after the parent key. Keeping the control
+            # tag itself at column zero prevents its indentation from leaking
+            # into the rendered YAML and nesting the next top-level key.
+            lines.append(f"{{% for {item_var} in {collection_var} %}}{item_lines[0]}")
+            lines.extend(item_lines[1:])
+            lines.append("{% endfor %}")
+        else:
+            lines.append(f"{{% for {item_var} in {collection_var} %}}")
+            lines.append("{% endfor %}")
 
         return "\n".join(lines) + "\n"
 

tests/test_yaml_handler.py

@@ -119,3 +119,48 @@ def test_yaml_empty_collection_defaults_match_template_vars(tmp_path: Path):
     )
     assert "{{ role_ignore }}" in template
     assert "{{ role_settings }}" in template
+
+
+def test_yaml_indentless_sequence_loop_roundtrips_semantically(tmp_path: Path):
+    """Indentless YAML sequences under a mapping key must be fully replaced.
+
+    A previous loop renderer emitted a loop at ``images:`` but then processed
+    the original ``- item`` lines again because they had the same indentation
+    as the parent key. That duplicated values and nested following top-level
+    keys incorrectly.
+    """
+    from jinja2 import Template
+
+    from jinjaturtle.core import analyze_loops
+
+    text = textwrap.dedent(
+        """
+        default:
+          provisioner: docker
+          images:
+          - waffleimage/ubuntu18.04
+          - waffleimage/centos7
+        vagrant:
+          provisioner: vagrant
+          images:
+          - centos/7
+          - generic/ubuntu1804
+        """
+    ).lstrip()
+    path = tmp_path / "provision.yaml"
+    path.write_text(text, encoding="utf-8")
+
+    fmt, parsed = parse_config(path)
+    loop_candidates = analyze_loops(fmt, parsed)
+    flat_items = flatten_config(fmt, parsed, loop_candidates)
+    defaults = yaml.safe_load(
+        generate_ansible_yaml("role", flat_items, loop_candidates)
+    )
+    template = generate_jinja2_template(
+        fmt, parsed, "role", original_text=text, loop_candidates=loop_candidates
+    )
+    rendered = Template(template).render(**defaults)
+
+    assert yaml.safe_load(rendered) == yaml.safe_load(text)
+    assert "      - waffleimage/ubuntu18.04" not in template
+    assert "  vagrant:" not in template