FilePersistence Namespace Reference

Thes FilePersistence plug-in implements a file and a clipboard application tree stores based on XML. More...

Classes
class	addAndRename
class	AtomicCycleMoveDel
class	AtomicCycleMoveIns
class	AtomicCycleMoveMove
class	BothChangeSameList_Conflicts
class	ChangeDescription
class	ChangeGraph
struct	Chunk
class	Commit
struct	CommitFile
class	CommitGraph
struct	CommitGraphItem
struct	CommitMetaData
class	Conflicts
class	ConflictUnitComponent
class	CopyPartialToClipboard
class	CopyToClipboard
class	deletion
class	Dependencies
class	Diff
class	Diff3Parse
class	DiscardConflictingDeletesComponent
	The DiscardConflictingDeletesComponent detects subtrees which one branch removes entirely and another alters. More...
class	EvalClassMove
class	EvalLoopFix
class	EvalMethodInsert
class	FilePersistenceException
class	FilePersistencePlugin
class	FileUtil
class	GenericNode
class	GenericPersistentUnit
class	GenericTree
	TODO It might be good to separate trees with piecewise loaders and other "kinds" of trees into subclasses. More...
struct	GitCommitExtract
struct	GitDiffExtract
class	GitPiecewiseLoader
class	GitRepository
class	History
class	insert
class	intValueChange
class	ListMergeComponent
class	listReorder
class	ListsReorderInsertDeleteResolvable
class	LoadingFullList
class	LoadingPartialList
class	LoadingTypedList
class	LoadModeNodesSingleUnitOnly
class	LoadMultipleUnits
class	LoadRootOnly
class	Merge
class	MergeChange
struct	MergeData
class	MergePipelineComponent
class	MoveAndListChangesResolvable
class	MoveChangeBetweenListsResolvable
class	MoveChangeBySingleVersion
class	MoveCycleSimple
class	MoveInAndListChangesResolvable
class	MoveVsInsertConflict
class	noChange
struct	NodeData
class	parentChange
class	Parser
class	PasteBinaryFromClipboard
class	PasteInListFromClipboard
class	PasteListFromClipboard
class	PasteTextFromClipboard
class	PiecewiseLoader
struct	RelativePathData
class	RunMerge
	The RunMerge test is not an actual test but rather is used to run the merge algorithm on the repo found in /tmp/EnvisionVC/TestMerge. More...
class	SaveModeNodesSingleUnitOnly
class	SaveMultipleUnits
class	SaveRootOnly
class	SavingTypedList
struct	Signature
class	SimpleTextFileStore
class	SingleVersionChange
class	SoftConflict
class	stmtEdit
class	SystemClipboard
class	TwoChangesDifferentLists
class	TwoChangesDifferentLists_LabelCycle
class	TwoChangesSameList
class	TwoChangesSameList_DelInsNodes
class	TwoChangesSameList_LabelCycleResolvable
class	TwoDeletesInSameListResolvable
class	TwoDeletesNoConflict
class	typeChange
class	UnorderedAndUnitsConflicting
class	VCTestProject
class	XMLModel

Typedefs
using	CommitFileContentDeleter = std::function< void(char *)>
using	IdToChangeDescriptionHash = QMultiHash< Model::NodeIdType, std::shared_ptr< ChangeDescription > >
using	IdToGenericNodeHash = QMultiHash< Model::NodeIdType, GenericNode * >

Enumerations
enum class	ChangeType { Unclassified , Insertion , Deletion , Move , Stationary }

Functions
static void	createNodeAndAppend (const git_diff_line *line, const char *filePath, GenericTree *tree, QList< GenericNode * > &list)
	libgit callback More...
static int	gitDiffExtractFileCallBack (const git_diff_delta *delta, float, void *carryAlongData)
	libgit callback More...
static int	gitDiffExtractLineCallBack (const git_diff_delta *delta, const git_diff_hunk *, const git_diff_line *line, void *carryAlongData)
	libgit callback More...
uint	qHash (const std::shared_ptr< const ChangeDescription > change, uint seed=0)
static int	relativePathTreeWalkCallBack (const char *root, const git_tree_entry *entry, void *data)
static int	treeWalkCommitExtractCallBack (const char *root, const git_tree_entry *entry, void *walkData)
	libgit callback: Tree Walk Callback More...

Variables
static const QString	CLIPBOARD_TAG = "clipboard"
static const int	MAX_DOUBLE_PRECISION = 15

Detailed Description

Thes FilePersistence plug-in implements a file and a clipboard application tree stores based on XML.

With the help of the SimpleTextFileStore class a tree can be stored as files on disk, where each persistence unit is saved to a different file. The precise data format is described below.

The SystemClipboard class provides access to the system clipboard. It offers functionality to copy a node or a list of nodes to the clipboard. Nodes are copied as an XML text which is described below. Nodes from the clipboard can be pasted into a node of a list type or can be used to replace other nodes in the tree.

Data persistence format

When application trees are stored on disk using the SimpleTextFileStore persistent store they are stored in a series of text files. To describe the format of these files we will use the simple application tree shown in the figure below.

A binary node hierarchy with a persistent unit

The image shows an application tree called units that contains 8 nodes. During the store operation each node is assigned a universally unique id (uuid) of the form {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} where each 'x' is a hex digit. In the documentation below we will use just integers as ids to simplify the presentation. The ids are indicated in the corresponding circle. Nodes 0,2,4 and 6 are of type BinaryNode. A binary node always has a name an optionally has a left and right nodes. The name is just a string. Node 2 in the figure is a persistence unit. Persistence units are saved in separate files by the SimpleTextFileStore class.

There is a master file which belongs to the main persistence unit (the application tree) and a file for each other persistence unit if any. Here is an example of a master file:

units BinaryNode {0xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
   name Text {1xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}. S_root
   left persistencenewunit {2xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
   right BinaryNode {4xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
      name Text {5xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}. S_second

Each line contains exactly one node from the tree. Child nodes are indented by tabs. The line defining a node has the following elements:

• name - the name by which the parrent refers to this child. For list parents, this is just the index in the list. For composite parents, this is the child attribute name. E.g. the then branch of an if statement has the name 'thenBranch'. The name of the root node is the application name. Some programming constructs have names independent of their parents. For example a method appears at a specific index in the list of methods of its parent, but has a separate name (e.g. foo). This name is encoded as a child attribute of the method, the attribute is of type NameText.
• type - this is the type of the node.
• id - the uuid of the node.
• (optional) value - leaf nodes have a value and no children. Leaf nodes have a '.' immediately after the uuid which is followed by a single space and a value type specifier. Specifiers are 'S_', 'I_' or 'D_' for String, Integer and Double respectively. The value follows immediately after the specifier. Integers and Doubles are encoded in decimal notation, Doubles use a decimal dot. Strings are encoded in unicode. Back slash '\', carriage return '\r' and new line feed '\n' are escaped with a single back slash character. Strings last until the end of the line.

persistencenewunit is a special node which indicates that its content is defined in a different file. The type of this node is also defined in that file. The file name is the uuid of the file, inlcuding the braces. In the example above this filename is {2xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}. Here is the content of that file:

left BinaryNodePersistenceUnit {2xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
   name Text {3xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}. S_first
   left BinaryNode {6xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
      name Text {7xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}. S_last

Its structure is identical to the one of the master file. top-level element which is absent. It is possible to have nested persistence unit nodes, in which case each new unit will be saved in its own file.

Format of the clipboard store

When using the ClipboardStore class provided by FilePersistence any copied nodes are stored as XML in the system clipboard. The format is equivalent to the one for persisting the tree on disk - we plan to unify the two in the future, they only diverge for historical reasons. Here is an example of two nodes being copied to clipboard:

<!DOCTYPE EnvisionFilePersistence>
<clipboard>
   <BinaryNode name="0" partial="0">
      <Text name="name" partial="0">S_first</Text>
   </BinaryNode>
   <BinaryNode name="1" partial="0">
      <Text name="name" partial="0">S_second</Text>
   </BinaryNode>
</clipboard>

The main element is clipboard and it contains one sub-element for each node that was copied. The structure of these sub-node elements is similar to the one discussed above, with the following differences:

• There is no node id attribute.
• The partial hint is always set to 0. Nodes loaded from the clipboard cannot be partially loaded.
• For direct children of clipboard the name attribute is simply an index that ranges from 0 to one less than the number of nodes copied to the clipboard.

Typedef Documentation

CommitFileContentDeleter

using FilePersistence::CommitFileContentDeleter = typedef std::function<void (char*)>

IdToChangeDescriptionHash

using FilePersistence::IdToChangeDescriptionHash = typedef QMultiHash<Model::NodeIdType, std::shared_ptr<ChangeDescription> >

IdToGenericNodeHash

using FilePersistence::IdToGenericNodeHash = typedef QMultiHash<Model::NodeIdType, GenericNode*>

Enumeration Type Documentation

ChangeType

enum FilePersistence::ChangeType

strong

Enumerator
Unclassified
Insertion
Deletion
Move
Stationary

Function Documentation

createNodeAndAppend()

static void FilePersistence::createNodeAndAppend ( const git_diff_line *  line, const char *  filePath, GenericTree *  tree, QList< GenericNode * > &  list  )

static

libgit callback

gitDiffExtractFileCallBack()

static int FilePersistence::gitDiffExtractFileCallBack ( const git_diff_delta *  delta, float  , void *  carryAlongData  )

static

libgit callback

gitDiffExtractLineCallBack()

static int FilePersistence::gitDiffExtractLineCallBack ( const git_diff_delta *  delta, const git_diff_hunk *  , const git_diff_line *  line, void *  carryAlongData  )

static

libgit callback

qHash()

uint FilePersistence::qHash ( const std::shared_ptr< const ChangeDescription >  change, uint  seed = 0  )

inline

relativePathTreeWalkCallBack()

static int FilePersistence::relativePathTreeWalkCallBack ( const char *  root, const git_tree_entry *  entry, void *  data  )

static

treeWalkCommitExtractCallBack()

static int FilePersistence::treeWalkCommitExtractCallBack ( const char *  root, const git_tree_entry *  entry, void *  walkData  )

static

libgit callback: Tree Walk Callback

Variable Documentation

CLIPBOARD_TAG

const QString FilePersistence::CLIPBOARD_TAG = "clipboard"

static

MAX_DOUBLE_PRECISION

const int FilePersistence::MAX_DOUBLE_PRECISION = 15

static