_yaml: Split Node-related parts into 'node.pyx'

This makes the 'Node' API public, and available for use directly for
plugins.

3 files changed, 22 insertions, 21 deletions

diff --git a/src/buildstream/_loader/loader.py b/src/buildstream/_loader/loader.py
index 27975dc34..5a2624c6a 100644
--- a/src/buildstream/_loader/loader.py
+++ b/src/buildstream/_loader/loader.py
@@ -24,6 +24,7 @@ from .._exceptions import LoadError, LoadErrorReason
 from .. import Consistency
 from .. import _yaml
 from ..element import Element
+from ..node import Node
 from .._profile import Topics, PROFILER
 from .._includes import Includes
 
@@ -120,7 +121,7 @@ class Loader():
 
         # Set up a dummy element that depends on all top-level targets
         # to resolve potential circular dependencies between them
-        dummy_target = LoadElement(_yaml.Node.from_dict({}), "", self)
+        dummy_target = LoadElement(Node.from_dict({}), "", self)
         dummy_target.dependencies.extend(
             LoadElement.Dependency(element, Symbol.RUNTIME)
             for element in target_elements
diff --git a/src/buildstream/_loader/metaelement.py b/src/buildstream/_loader/metaelement.py
index 8214e303d..67d2ec771 100644
--- a/src/buildstream/_loader/metaelement.py
+++ b/src/buildstream/_loader/metaelement.py
@@ -17,7 +17,7 @@
 #  Authors:
 #        Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
 
-from .. import _yaml
+from ..node import Node
 
 
 class MetaElement():
@@ -48,12 +48,12 @@ class MetaElement():
         self.kind = kind
         self.provenance = provenance
         self.sources = sources
-        self.config = config or _yaml.Node.from_dict({})
-        self.variables = variables or _yaml.Node.from_dict({})
-        self.environment = environment or _yaml.Node.from_dict({})
+        self.config = config or Node.from_dict({})
+        self.variables = variables or Node.from_dict({})
+        self.environment = environment or Node.from_dict({})
         self.env_nocache = env_nocache or []
-        self.public = public or _yaml.Node.from_dict({})
-        self.sandbox = sandbox or _yaml.Node.from_dict({})
+        self.public = public or Node.from_dict({})
+        self.sandbox = sandbox or Node.from_dict({})
         self.build_dependencies = []
         self.dependencies = []
         self.first_pass = first_pass
diff --git a/src/buildstream/_loader/types.pyx b/src/buildstream/_loader/types.pyx
index fe1cea789..e8c16b36e 100644
--- a/src/buildstream/_loader/types.pyx
+++ b/src/buildstream/_loader/types.pyx
@@ -18,7 +18,7 @@
 #        Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
 
 from .._exceptions import LoadError, LoadErrorReason
-from .. cimport _yaml
+from ..node cimport MappingNode, Node, ProvenanceInformation, ScalarNode, SequenceNode
 
 
 # Symbol():
@@ -59,32 +59,32 @@ class Symbol():
 #                                        dependency was declared
 #
 cdef class Dependency:
-    cdef public _yaml.ProvenanceInformation provenance
+    cdef public ProvenanceInformation provenance
     cdef public str name
     cdef public str dep_type
     cdef public str junction
 
     def __init__(self,
-                 _yaml.Node dep,
+                 Node dep,
                  str default_dep_type=None):
         cdef str dep_type
 
         self.provenance = dep.get_provenance()
 
-        if type(dep) is _yaml.ScalarNode:
+        if type(dep) is ScalarNode:
             self.name = dep.as_str()
             self.dep_type = default_dep_type
             self.junction = None
 
-        elif type(dep) is _yaml.MappingNode:
+        elif type(dep) is MappingNode:
             if default_dep_type:
-                (<_yaml.MappingNode> dep).validate_keys(['filename', 'junction'])
+                (<MappingNode> dep).validate_keys(['filename', 'junction'])
                 dep_type = default_dep_type
             else:
-                (<_yaml.MappingNode> dep).validate_keys(['filename', 'type', 'junction'])
+                (<MappingNode> dep).validate_keys(['filename', 'type', 'junction'])
 
                 # Make type optional, for this we set it to None
-                dep_type = (<_yaml.MappingNode> dep).get_str(<str> Symbol.TYPE, None)
+                dep_type = (<MappingNode> dep).get_str(<str> Symbol.TYPE, None)
                 if dep_type is None or dep_type == <str> Symbol.ALL:
                     dep_type = None
                 elif dep_type not in [Symbol.BUILD, Symbol.RUNTIME]:
@@ -93,9 +93,9 @@ cdef class Dependency:
                                     "{}: Dependency type '{}' is not 'build', 'runtime' or 'all'"
                                     .format(provenance, dep_type))
 
-            self.name = (<_yaml.MappingNode> dep).get_str(<str> Symbol.FILENAME)
+            self.name = (<MappingNode> dep).get_str(<str> Symbol.FILENAME)
             self.dep_type = dep_type
-            self.junction = (<_yaml.MappingNode> dep).get_str(<str> Symbol.JUNCTION, None)
+            self.junction = (<MappingNode> dep).get_str(<str> Symbol.JUNCTION, None)
 
         else:
             raise LoadError(LoadErrorReason.INVALID_DATA,
@@ -136,9 +136,9 @@ cdef class Dependency:
 #    default_dep_type (str): type to give to the dependency
 #    acc (list): a list in which to add the loaded dependencies
 #
-cdef void _extract_depends_from_node(_yaml.Node node, str key, str default_dep_type, list acc) except *:
-    cdef _yaml.SequenceNode depends = node.get_sequence(key, [])
-    cdef _yaml.Node dep_node
+cdef void _extract_depends_from_node(Node node, str key, str default_dep_type, list acc) except *:
+    cdef SequenceNode depends = node.get_sequence(key, [])
+    cdef Node dep_node
 
     for dep_node in depends:
         dependency = Dependency(dep_node, default_dep_type=default_dep_type)
@@ -162,7 +162,7 @@ cdef void _extract_depends_from_node(_yaml.Node node, str key, str default_dep_t
 # Returns:
 #    (list): a list of Dependency objects
 #
-def extract_depends_from_node(_yaml.Node node):
+def extract_depends_from_node(Node node):
     cdef list acc = []
     _extract_depends_from_node(node, <str> Symbol.BUILD_DEPENDS, <str> Symbol.BUILD, acc)
     _extract_depends_from_node(node, <str> Symbol.RUNTIME_DEPENDS, <str> Symbol.RUNTIME, acc)