tests/yaml/, tests/format/: Added tests for list composition directives

16 files changed, 324 insertions, 104 deletions

diff --git a/tests/format/list-directive-error-element/config.bst b/tests/format/list-directive-error-element/config.bst
new file mode 100644
index 000000000..f2d6a985a
--- /dev/null
+++ b/tests/format/list-directive-error-element/config.bst
@@ -0,0 +1,7 @@
+kind: autotools
+
+config:
+  outigration-frob-mans:
+    (>):
+    - name: Appending to something
+    - value: that is not integration-commands
diff --git a/tests/format/list-directive-error-element/environment.bst b/tests/format/list-directive-error-element/environment.bst
new file mode 100644
index 000000000..7a88e1a11
--- /dev/null
+++ b/tests/format/list-directive-error-element/environment.bst
@@ -0,0 +1,7 @@
+kind: autotools
+
+environment:
+  foo:
+    (=):
+    - name: Overriding
+    - value: Something that doesnt exist
diff --git a/tests/format/list-directive-error-element/project.conf b/tests/format/list-directive-error-element/project.conf
new file mode 100644
index 000000000..b32753625
--- /dev/null
+++ b/tests/format/list-directive-error-element/project.conf
@@ -0,0 +1 @@
+name: test
diff --git a/tests/format/list-directive-error-element/public.bst b/tests/format/list-directive-error-element/public.bst
new file mode 100644
index 000000000..8e49218be
--- /dev/null
+++ b/tests/format/list-directive-error-element/public.bst
@@ -0,0 +1,8 @@
+kind: autotools
+
+public:
+  foo:
+    the-foo-list:
+      (>):
+      - name: Appending to something
+      - value: that does not exist
diff --git a/tests/format/list-directive-error-element/variables.bst b/tests/format/list-directive-error-element/variables.bst
new file mode 100644
index 000000000..0a88d5fa7
--- /dev/null
+++ b/tests/format/list-directive-error-element/variables.bst
@@ -0,0 +1,7 @@
+kind: autotools
+
+variables:
+  foo:
+    (<):
+    - name: Prepending
+    - value: To something that doesnt exist
diff --git a/tests/format/list-directive-error-project/element.bst b/tests/format/list-directive-error-project/element.bst
new file mode 100644
index 000000000..3c29b4ea1
--- /dev/null
+++ b/tests/format/list-directive-error-project/element.bst
@@ -0,0 +1 @@
+kind: autotools
diff --git a/tests/format/list-directive-error-project/project.conf b/tests/format/list-directive-error-project/project.conf
new file mode 100644
index 000000000..dfba68b98
--- /dev/null
+++ b/tests/format/list-directive-error-project/project.conf
@@ -0,0 +1,6 @@
+name: test
+
+non-existant:
+  (>):
+  - name: Appending
+  - value: To something that doesnt exist
diff --git a/tests/format/listdirectiveerrors.py b/tests/format/listdirectiveerrors.py
new file mode 100644
index 000000000..001b8a49d
--- /dev/null
+++ b/tests/format/listdirectiveerrors.py
@@ -0,0 +1,41 @@
+import os
+import pytest
+from buildstream import _yaml
+from buildstream import LoadError, LoadErrorReason
+from tests.testutils.runcli import cli
+
+# Project directory
+DATA_DIR = os.path.dirname(os.path.realpath(__file__))
+
+
+@pytest.mark.datafiles(DATA_DIR)
+def test_project_error(cli, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename, 'list-directive-error-project')
+    result = cli.run(project=project, silent=True, args=[
+        'show',
+        '--deps', 'none',
+        '--format', '%{vars}',
+        'element.bst'])
+
+    assert result.exit_code != 0
+    assert result.exception
+    assert isinstance(result.exception, LoadError)
+    assert result.exception.reason == LoadErrorReason.TRAILING_LIST_DIRECTIVE
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("target", [
+    ('variables.bst'), ('environment.bst'), ('config.bst'), ('public.bst')
+])
+def test_element_error(cli, datafiles, target):
+    project = os.path.join(datafiles.dirname, datafiles.basename, 'list-directive-error-element')
+    result = cli.run(project=project, silent=True, args=[
+        'show',
+        '--deps', 'none',
+        '--format', '%{vars}',
+        target])
+
+    assert result.exit_code != 0
+    assert result.exception
+    assert isinstance(result.exception, LoadError)
+    assert result.exception.reason == LoadErrorReason.TRAILING_LIST_DIRECTIVE
diff --git a/tests/yaml/data/implicitoverwrite.yaml b/tests/yaml/data/implicitoverwrite.yaml
new file mode 100644
index 000000000..20e5eb76a
--- /dev/null
+++ b/tests/yaml/data/implicitoverwrite.yaml
@@ -0,0 +1,6 @@
+# Composited on top of basics.yaml, overwriting it's children list
+children:
+- name: overwrite1
+  mood: overwrite1
+- name: overwrite2
+  mood: overwrite2
diff --git a/tests/yaml/data/listappend.yaml b/tests/yaml/data/listappend.yaml
new file mode 100644
index 000000000..889ed80b2
--- /dev/null
+++ b/tests/yaml/data/listappend.yaml
@@ -0,0 +1,7 @@
+# Composited on top of basics.yaml, appending to it's children list
+children:
+  (>):
+  - name: appended1
+    mood: appended1
+  - name: appended2
+    mood: appended2
diff --git a/tests/yaml/data/listappendprepend.yaml b/tests/yaml/data/listappendprepend.yaml
new file mode 100644
index 000000000..18471b36c
--- /dev/null
+++ b/tests/yaml/data/listappendprepend.yaml
@@ -0,0 +1,12 @@
+# Composited on top of basics.yaml, prepending and appending to it's children list
+children:
+  (<):
+  - name: prepended1
+    mood: prepended1
+  - name: prepended2
+    mood: prepended2
+  (>):
+  - name: appended1
+    mood: appended1
+  - name: appended2
+    mood: appended2
diff --git a/tests/yaml/data/listoverwrite.yaml b/tests/yaml/data/listoverwrite.yaml
new file mode 100644
index 000000000..3efdfa7cb
--- /dev/null
+++ b/tests/yaml/data/listoverwrite.yaml
@@ -0,0 +1,7 @@
+# Composited on top of basics.yaml, overwriting it's children list
+children:
+  (=):
+  - name: overwrite1
+    mood: overwrite1
+  - name: overwrite2
+    mood: overwrite2
diff --git a/tests/yaml/data/listprepend.yaml b/tests/yaml/data/listprepend.yaml
new file mode 100644
index 000000000..3934c93be
--- /dev/null
+++ b/tests/yaml/data/listprepend.yaml
@@ -0,0 +1,7 @@
+# Composited on top of basics.yaml, prepending to it's children list
+children:
+  (<):
+  - name: prepended1
+    mood: prepended1
+  - name: prepended2
+    mood: prepended2
diff --git a/tests/yaml/data/secondappend.yaml b/tests/yaml/data/secondappend.yaml
new file mode 100644
index 000000000..376c4a707
--- /dev/null
+++ b/tests/yaml/data/secondappend.yaml
@@ -0,0 +1,7 @@
+# Composited on top of listappend.yaml, appending to it's children list
+children:
+  (>):
+  - name: secondappend1
+    mood: secondappend1
+  - name: secondappend2
+    mood: secondappend2
diff --git a/tests/yaml/data/secondprepend.yaml b/tests/yaml/data/secondprepend.yaml
new file mode 100644
index 000000000..58276c381
--- /dev/null
+++ b/tests/yaml/data/secondprepend.yaml
@@ -0,0 +1,7 @@
+# Composited on top of listprepend.yaml, prepending to it's children list
+children:
+  (<):
+  - name: secondprepend1
+    mood: secondprepend1
+  - name: secondprepend2
+    mood: secondprepend2
diff --git a/tests/yaml/yaml.py b/tests/yaml/yaml.py
index 948151bed..cf12317a9 100644
--- a/tests/yaml/yaml.py
+++ b/tests/yaml/yaml.py
@@ -4,7 +4,6 @@ from collections import Mapping
 
 from buildstream import _yaml
 from buildstream import LoadError, LoadErrorReason
-from buildstream._yaml import CompositePolicy
 
 DATA_DIR = os.path.join(
     os.path.dirname(os.path.realpath(__file__)),
@@ -77,92 +76,6 @@ def test_element_provenance(datafiles):
 
 
 @pytest.mark.datafiles(os.path.join(DATA_DIR))
-def test_composited_overwrite_provenance(datafiles):
-
-    filename = os.path.join(datafiles.dirname,
-                            datafiles.basename,
-                            'basics.yaml')
-    overlayfile = os.path.join(datafiles.dirname,
-                               datafiles.basename,
-                               'composite.yaml')
-
-    base = _yaml.load(filename)
-    assert(base.get('kind') == 'pony')
-    assert_provenance(filename, 1, 0, base)
-
-    overlay = _yaml.load(overlayfile)
-    assert(overlay.get('kind') == 'horse')
-    assert_provenance(overlayfile, 1, 0, overlay)
-
-    _yaml.composite_dict(base, overlay,
-                         policy=CompositePolicy.OVERWRITE, typesafe=True)
-    assert(base.get('kind') == 'horse')
-
-    children = base.get('children')
-    assert(isinstance(children, list))
-    assert(len(children) == 1)
-
-    assert_provenance(filename, 1, 0, base)
-
-    # The entire children member is overwritten with the overlay
-    assert_provenance(overlayfile, 4, 0, base, 'children')
-    assert_provenance(overlayfile, 4, 2, base, 'children', [0])
-
-    # The child dict itself has the overlay provenance
-    child = children[0]
-    assert_provenance(overlayfile, 5, 8, child, 'mood')
-
-
-@pytest.mark.datafiles(os.path.join(DATA_DIR))
-def test_composited_array_append_provenance(datafiles):
-
-    filename = os.path.join(datafiles.dirname,
-                            datafiles.basename,
-                            'basics.yaml')
-    overlayfile = os.path.join(datafiles.dirname,
-                               datafiles.basename,
-                               'composite.yaml')
-
-    base = _yaml.load(filename)
-    assert(base.get('kind') == 'pony')
-    assert_provenance(filename, 1, 0, base)
-
-    overlay = _yaml.load(overlayfile)
-    assert(overlay.get('kind') == 'horse')
-    assert_provenance(overlayfile, 1, 0, overlay)
-
-    _yaml.composite_dict(base, overlay,
-                         policy=CompositePolicy.ARRAY_APPEND, typesafe=True)
-    assert(base.get('kind') == 'horse')
-
-    children = base.get('children')
-    assert(isinstance(children, list))
-    assert(len(children) == 8)
-
-    assert_provenance(filename, 1, 0, base)
-    assert_provenance(filename, 7, 0, base, 'children')
-
-    # The newly added element has the overlay provenance
-    assert_provenance(overlayfile, 4, 2, base, 'children', [7])
-
-    # The child dict itself has the overlay provenance
-    child = children[7]
-    assert_provenance(overlayfile, 5, 8, child, 'mood')
-
-    extra = base.get('extra')
-    assert(isinstance(extra, dict))
-    another = extra.get('another')
-    assert(isinstance(another, dict))
-
-    assert_provenance(filename, 22, 2, base, 'extra')
-    assert_provenance(filename, 22, 2, extra)
-    assert_provenance(filename, 22, 8, extra, 'this')
-
-    assert_provenance(overlayfile, 9, 4, extra, 'another')
-    assert_provenance(overlayfile, 9, 4, another)
-
-
-@pytest.mark.datafiles(os.path.join(DATA_DIR))
 def test_node_validate(datafiles):
 
     valid = os.path.join(datafiles.dirname,
@@ -190,31 +103,20 @@ def test_node_get(datafiles):
     filename = os.path.join(datafiles.dirname,
                             datafiles.basename,
                             'basics.yaml')
-    overlayfile = os.path.join(datafiles.dirname,
-                               datafiles.basename,
-                               'composite.yaml')
 
     base = _yaml.load(filename)
     assert(base.get('kind') == 'pony')
-    overlay = _yaml.load(overlayfile)
-    assert(overlay.get('kind') == 'horse')
-    _yaml.composite_dict(base, overlay,
-                         policy=CompositePolicy.ARRAY_APPEND,
-                         typesafe=True)
-    assert(base.get('kind') == 'horse')
 
     children = _yaml.node_get(base, list, 'children')
     assert(isinstance(children, list))
-    assert(len(children) == 8)
+    assert(len(children) == 7)
 
-    child = _yaml.node_get(base, Mapping, 'children', indices=[7])
-    assert_provenance(overlayfile, 5, 8, child, 'mood')
+    child = _yaml.node_get(base, Mapping, 'children', indices=[6])
+    assert_provenance(filename, 20, 8, child, 'mood')
 
     extra = _yaml.node_get(base, Mapping, 'extra')
-    another = _yaml.node_get(extra, Mapping, 'another')
-
     with pytest.raises(LoadError) as exc:
-        wrong = _yaml.node_get(another, Mapping, 'five')
+        wrong = _yaml.node_get(extra, Mapping, 'old')
 
     assert (exc.value.reason == LoadErrorReason.INVALID_DATA)
 
@@ -236,8 +138,7 @@ def test_composite_preserve_originals(datafiles):
     base = _yaml.load(filename)
     overlay = _yaml.load(overlayfile)
     base_copy = _yaml.node_chain_copy(base)
-    _yaml.composite_dict(base_copy, overlay,
-                         policy=CompositePolicy.OVERWRITE, typesafe=True)
+    _yaml.composite_dict(base_copy, overlay)
 
     copy_extra = _yaml.node_get(base_copy, Mapping, 'extra')
     orig_extra = _yaml.node_get(base, Mapping, 'extra')
@@ -247,3 +148,191 @@ def test_composite_preserve_originals(datafiles):
 
     # But the original node is not effected by the override.
     assert(_yaml.node_get(orig_extra, str, 'old') == 'new')
+
+
+# Tests for list composition
+#
+# Each test composits a filename on top of basics.yaml, and tests
+# the toplevel children list at the specified index
+#
+# Parameters:
+#    filename: The file to composite on top of basics.yaml
+#    index: The index in the children list
+#    length: The expected length of the children list
+#    mood: The expected value of the mood attribute of the dictionary found at index in children
+#    prov_file: The expected provenance filename of "mood"
+#    prov_line: The expected provenance line of "mood"
+#    prov_col: The expected provenance column of "mood"
+#
+@pytest.mark.datafiles(os.path.join(DATA_DIR))
+@pytest.mark.parametrize("filename,index,length,mood,prov_file,prov_line,prov_col", [
+
+    # Test results of compositing with the (<) prepend directive
+    ('listprepend.yaml', 0, 9, 'prepended1', 'listprepend.yaml', 5, 10),
+    ('listprepend.yaml', 1, 9, 'prepended2', 'listprepend.yaml', 7, 10),
+    ('listprepend.yaml', 2, 9, 'silly', 'basics.yaml', 8, 8),
+    ('listprepend.yaml', 8, 9, 'sleepy', 'basics.yaml', 20, 8),
+
+    # Test results of compositing with the (>) append directive
+    ('listappend.yaml', 7, 9, 'appended1', 'listappend.yaml', 5, 10),
+    ('listappend.yaml', 8, 9, 'appended2', 'listappend.yaml', 7, 10),
+    ('listappend.yaml', 0, 9, 'silly', 'basics.yaml', 8, 8),
+    ('listappend.yaml', 6, 9, 'sleepy', 'basics.yaml', 20, 8),
+
+    # Test results of compositing with both (<) and (>) directives
+    ('listappendprepend.yaml', 0, 11, 'prepended1', 'listappendprepend.yaml', 5, 10),
+    ('listappendprepend.yaml', 1, 11, 'prepended2', 'listappendprepend.yaml', 7, 10),
+    ('listappendprepend.yaml', 2, 11, 'silly', 'basics.yaml', 8, 8),
+    ('listappendprepend.yaml', 8, 11, 'sleepy', 'basics.yaml', 20, 8),
+    ('listappendprepend.yaml', 9, 11, 'appended1', 'listappendprepend.yaml', 10, 10),
+    ('listappendprepend.yaml', 10, 11, 'appended2', 'listappendprepend.yaml', 12, 10),
+
+    # Test results of compositing with the (=) overwrite directive
+    ('listoverwrite.yaml', 0, 2, 'overwrite1', 'listoverwrite.yaml', 5, 10),
+    ('listoverwrite.yaml', 1, 2, 'overwrite2', 'listoverwrite.yaml', 7, 10),
+
+    # Test results of compositing without any directive, implicitly overwriting
+    ('implicitoverwrite.yaml', 0, 2, 'overwrite1', 'implicitoverwrite.yaml', 4, 8),
+    ('implicitoverwrite.yaml', 1, 2, 'overwrite2', 'implicitoverwrite.yaml', 6, 8),
+])
+def test_list_composition(datafiles, filename,
+                          index, length, mood,
+                          prov_file, prov_line, prov_col):
+    base = os.path.join(datafiles.dirname, datafiles.basename, 'basics.yaml')
+    overlay = os.path.join(datafiles.dirname, datafiles.basename, filename)
+
+    base = _yaml.load(base, shortname='basics.yaml')
+    overlay = _yaml.load(overlay, shortname=filename)
+    _yaml.composite_dict(base, overlay)
+
+    children = _yaml.node_get(base, list, 'children')
+    assert len(children) == length
+    child = children[index]
+
+    assert child['mood'] == mood
+    assert_provenance(prov_file, prov_line, prov_col, child, 'mood')
+
+
+# Tests for deep list composition
+#
+# Same as test_list_composition(), but adds an additional file
+# in between so that lists are composited twice.
+#
+# This test will to two iterations for each parameter
+# specification, expecting the same results
+#
+#   First iteration:
+#      composited = basics.yaml & filename1
+#      composited = composited & filename2
+#
+#   Second iteration:
+#      composited = filename1 & filename2
+#      composited = basics.yaml & composited
+#
+# Parameters:
+#    filename1: The file to composite on top of basics.yaml
+#    filename2: The file to composite on top of filename1
+#    index: The index in the children list
+#    length: The expected length of the children list
+#    mood: The expected value of the mood attribute of the dictionary found at index in children
+#    prov_file: The expected provenance filename of "mood"
+#    prov_line: The expected provenance line of "mood"
+#    prov_col: The expected provenance column of "mood"
+#
+@pytest.mark.datafiles(os.path.join(DATA_DIR))
+@pytest.mark.parametrize("filename1,filename2,index,length,mood,prov_file,prov_line,prov_col", [
+
+    # Test results of compositing literal list with (>) and then (<)
+    ('listprepend.yaml', 'listappend.yaml', 0, 11, 'prepended1', 'listprepend.yaml', 5, 10),
+    ('listprepend.yaml', 'listappend.yaml', 1, 11, 'prepended2', 'listprepend.yaml', 7, 10),
+    ('listprepend.yaml', 'listappend.yaml', 2, 11, 'silly', 'basics.yaml', 8, 8),
+    ('listprepend.yaml', 'listappend.yaml', 8, 11, 'sleepy', 'basics.yaml', 20, 8),
+    ('listprepend.yaml', 'listappend.yaml', 9, 11, 'appended1', 'listappend.yaml', 5, 10),
+    ('listprepend.yaml', 'listappend.yaml', 10, 11, 'appended2', 'listappend.yaml', 7, 10),
+
+    # Test results of compositing literal list with (<) and then (>)
+    ('listappend.yaml', 'listprepend.yaml', 0, 11, 'prepended1', 'listprepend.yaml', 5, 10),
+    ('listappend.yaml', 'listprepend.yaml', 1, 11, 'prepended2', 'listprepend.yaml', 7, 10),
+    ('listappend.yaml', 'listprepend.yaml', 2, 11, 'silly', 'basics.yaml', 8, 8),
+    ('listappend.yaml', 'listprepend.yaml', 8, 11, 'sleepy', 'basics.yaml', 20, 8),
+    ('listappend.yaml', 'listprepend.yaml', 9, 11, 'appended1', 'listappend.yaml', 5, 10),
+    ('listappend.yaml', 'listprepend.yaml', 10, 11, 'appended2', 'listappend.yaml', 7, 10),
+
+    # Test results of compositing literal list with (>) and then (>)
+    ('listappend.yaml', 'secondappend.yaml', 0, 11, 'silly', 'basics.yaml', 8, 8),
+    ('listappend.yaml', 'secondappend.yaml', 6, 11, 'sleepy', 'basics.yaml', 20, 8),
+    ('listappend.yaml', 'secondappend.yaml', 7, 11, 'appended1', 'listappend.yaml', 5, 10),
+    ('listappend.yaml', 'secondappend.yaml', 8, 11, 'appended2', 'listappend.yaml', 7, 10),
+    ('listappend.yaml', 'secondappend.yaml', 9, 11, 'secondappend1', 'secondappend.yaml', 5, 10),
+    ('listappend.yaml', 'secondappend.yaml', 10, 11, 'secondappend2', 'secondappend.yaml', 7, 10),
+
+    # Test results of compositing literal list with (>) and then (>)
+    ('listprepend.yaml', 'secondprepend.yaml', 0, 11, 'secondprepend1', 'secondprepend.yaml', 5, 10),
+    ('listprepend.yaml', 'secondprepend.yaml', 1, 11, 'secondprepend2', 'secondprepend.yaml', 7, 10),
+    ('listprepend.yaml', 'secondprepend.yaml', 2, 11, 'prepended1', 'listprepend.yaml', 5, 10),
+    ('listprepend.yaml', 'secondprepend.yaml', 3, 11, 'prepended2', 'listprepend.yaml', 7, 10),
+    ('listprepend.yaml', 'secondprepend.yaml', 4, 11, 'silly', 'basics.yaml', 8, 8),
+    ('listprepend.yaml', 'secondprepend.yaml', 10, 11, 'sleepy', 'basics.yaml', 20, 8),
+
+    # Test results of compositing literal list with (>) or (<) and then another literal list
+    ('listappend.yaml', 'implicitoverwrite.yaml', 0, 2, 'overwrite1', 'implicitoverwrite.yaml', 4, 8),
+    ('listappend.yaml', 'implicitoverwrite.yaml', 1, 2, 'overwrite2', 'implicitoverwrite.yaml', 6, 8),
+    ('listprepend.yaml', 'implicitoverwrite.yaml', 0, 2, 'overwrite1', 'implicitoverwrite.yaml', 4, 8),
+    ('listprepend.yaml', 'implicitoverwrite.yaml', 1, 2, 'overwrite2', 'implicitoverwrite.yaml', 6, 8),
+
+    # Test results of compositing literal list with (>) or (<) and then an explicit (=) overwrite
+    ('listappend.yaml', 'listoverwrite.yaml', 0, 2, 'overwrite1', 'listoverwrite.yaml', 5, 10),
+    ('listappend.yaml', 'listoverwrite.yaml', 1, 2, 'overwrite2', 'listoverwrite.yaml', 7, 10),
+    ('listprepend.yaml', 'listoverwrite.yaml', 0, 2, 'overwrite1', 'listoverwrite.yaml', 5, 10),
+    ('listprepend.yaml', 'listoverwrite.yaml', 1, 2, 'overwrite2', 'listoverwrite.yaml', 7, 10),
+
+    # Test results of compositing literal list an explicit overwrite (=) and then with (>) or (<)
+    ('listoverwrite.yaml', 'listappend.yaml', 0, 4, 'overwrite1', 'listoverwrite.yaml', 5, 10),
+    ('listoverwrite.yaml', 'listappend.yaml', 1, 4, 'overwrite2', 'listoverwrite.yaml', 7, 10),
+    ('listoverwrite.yaml', 'listappend.yaml', 2, 4, 'appended1', 'listappend.yaml', 5, 10),
+    ('listoverwrite.yaml', 'listappend.yaml', 3, 4, 'appended2', 'listappend.yaml', 7, 10),
+    ('listoverwrite.yaml', 'listprepend.yaml', 0, 4, 'prepended1', 'listprepend.yaml', 5, 10),
+    ('listoverwrite.yaml', 'listprepend.yaml', 1, 4, 'prepended2', 'listprepend.yaml', 7, 10),
+    ('listoverwrite.yaml', 'listprepend.yaml', 2, 4, 'overwrite1', 'listoverwrite.yaml', 5, 10),
+    ('listoverwrite.yaml', 'listprepend.yaml', 3, 4, 'overwrite2', 'listoverwrite.yaml', 7, 10),
+])
+def test_list_composition_twice(datafiles, filename1, filename2,
+                                index, length, mood,
+                                prov_file, prov_line, prov_col):
+    file_base = os.path.join(datafiles.dirname, datafiles.basename, 'basics.yaml')
+    file1 = os.path.join(datafiles.dirname, datafiles.basename, filename1)
+    file2 = os.path.join(datafiles.dirname, datafiles.basename, filename2)
+
+    #####################
+    # Round 1 - Fight !
+    #####################
+    base = _yaml.load(file_base, shortname='basics.yaml')
+    overlay1 = _yaml.load(file1, shortname=filename1)
+    overlay2 = _yaml.load(file2, shortname=filename2)
+
+    _yaml.composite_dict(base, overlay1)
+    _yaml.composite_dict(base, overlay2)
+
+    children = _yaml.node_get(base, list, 'children')
+    assert len(children) == length
+    child = children[index]
+
+    assert child['mood'] == mood
+    assert_provenance(prov_file, prov_line, prov_col, child, 'mood')
+
+    #####################
+    # Round 2 - Fight !
+    #####################
+    base = _yaml.load(file_base, shortname='basics.yaml')
+    overlay1 = _yaml.load(file1, shortname=filename1)
+    overlay2 = _yaml.load(file2, shortname=filename2)
+
+    _yaml.composite_dict(overlay1, overlay2)
+    _yaml.composite_dict(base, overlay1)
+
+    children = _yaml.node_get(base, list, 'children')
+    assert len(children) == length
+    child = children[index]
+
+    assert child['mood'] == mood
+    assert_provenance(prov_file, prov_line, prov_col, child, 'mood')