Source code
Revision control
Copy as Markdown
Other Tools
(searchfox-diagramming)=
# Diagramming
The diagramming feature provides generating diagrams for calls/uses relations, classes and their inheritances.
The diagramming feature can be accessed from two ways.
- {ref}`Context menu <searchfox-diagramming-context-menu>`
- {ref}`Query endpoint <searchfox-diagramming-queries>`
**Enabling Diagramming**: To use diagramming features, visit the [settings page](https://searchfox.org/mozilla-central/pages/settings.html) and change the
"Default feature gate" from "Release" to "Alpha", or use the "Diagramming
feature gate" setting.
**Language Support**: Diagramming currently works for C++ and languages with
SCIP indexing support (Java/Kotlin/Python), but not JavaScript/TypeScript.
**Accessibility Note**: The diagrams currently do not generate a usable
accessibility tree and are considered alpha quality.
```{image} img/diagramming.png
:alt: The diagramming feature
:class: border
:width: 538px
```
(searchfox-diagramming-context-menu)=
## Context Menu
```{image} img/context-menu-diagram.png
:alt: The context menu for diagramming
:class: border
:width: 433px
```
Calls to
: Open a diagram that shows how given symbol is called or used.
Calls from
: Open a diagram that shows how given symbol uses other functions
Class
: Open a diagram that shows given class and its fields, the hierarchy, etc.
Inheritance
: Open a diagram that shows the class hierarchy of given class.
Pin icon
: Pin the symbol, to create a diagram between two symbols.
```{image} img/context-menu-diagram-pin.png
:alt: The context menu for diagramming with pinned item
:class: border
:width: 413px
```
When a symbol is pinned, another row of buttons are shown.
Calls from Pin to
: Open a diagram that shows the paths from the pinned symbol to the clicked symbol
Calls to Pin from
: Open a diagram that shows the paths from the clicked symbol to the pinned symbol
Calls between
: Open a diagram that shows the paths between the clicked symbol and the pinned symbol, for both directions
Trash icon
: Remove the pinned symbol
### Context Menu for nodes
```{image} img/diagramming-menu-node.png
:alt: The context menu for nodes
:class: border
:width: 463px
```
Ignore this node in the diagram
: Re-generate the diagram, ignoring the specified node.
### Context Menu for edges
```{image} img/diagramming-menu-edge.png
:alt: The context menu for edges
:class: border
:width: 426px
```
Go to use of ...
: Open the use site of the function shown as the edge.
(searchfox-diagramming-queries)=
## Controls
In the diagramming page, the breadcrumbs contains the "Diagram Controls" button.
The control panel allows customizing the query.
The number of nodes are limited by default. If the limit is hit, warning messages are shown, with buttons to lift the limit if possible.
The Legend section shows the meaning of the badges (e.g. "💪"), which can be added to the nodes for annotation purposes.
```{image} img/diagramming-control.png
:alt: The control panel
:class: border
:width: 919px
```
Depth
: Limit graph traversal to N levels of depth (1-based).
Corresponds to the `depth:N` parameter.
Node limit
: Maximum nodes in resulting graph.
Corresponds to the `node-limit:N` parameter.
Path limit
: Nodes with more than N in-edges will be excluded (default: 96)
For "Calls between", this is maximum nodes for path-finding algorithm
Corresponds to either the `path-limit:N` or the
`paths-between-node-limit:N` parameter.
Ignore nodes
: A comma-separated list of pretty symbols for the nodes to exclude from the diagram.
This can be added by the "Ignore this node in the diagram" context menu item.
Corresponds to the `ignore-nodes:LIST` parameter.
Hierarchy
: Controls the hierarchy and the styling of the diagram.
Simple no hierarchy
: Disable hierarchy, use old flat layout (`hier:flat`)
No hierarchy
: Disable hierarchy but applies other styling, such as badges (`hier:flatbadges`)
Pretty identifier hierarchy
: Default hierarchy based on pretty symbol name (`hier:pretty`)
Subsystem and class structures:
: Group by bugzilla component mapping (`hier:subsystem`)
Full file paths
: Fine-grained file-level hierarchy (`hier:file`)
Directories
: Group by directories (`hier:dir`)
Layout
: Select the layout algorithm.
dot
: Default orderly layout (recommended) (`graph-layout:dot`)
neato
: Force-directed layout for less orderly appearance (`graph-layout:neato`)
fdp
: Force-directed with variable edge lengths (`graph-layout:fdp`)
Format
: Select the output format of the graph.
Options other than "SVG and symbols" are mostly for debugging purpose.
JSON
: Prints the raw input JSON data for the graph (`graph-format:json`)
SVG
: Shows only the generated SVG (`graph-format:svg`)
dot with layout
: Prints the raw "dot" input data, with the layout information (`graph-format:dot`)
dot without layout
: Prints the raw "dot" input data, without the layout information ( `graph-format:raw-dot`
SVG and symbols
: Show the generated SVG, annotated with the symbol information `graph-format:mozsearch`
Debug
: When checked, show the debug log.
## Icons
To reduce the server load, the diagramming feature has several limitation,
and when it hits the limit, icons are shown for each node.
Clicking the icon shows a menu to lift the limit if possible.
See also the controls section above.
```{image} img/diagramming-icons.png
:alt: The control panel
:class: border
:width: 296px
```
Circle with "!"
: This node hits the depth limit.
Triangle with "!"
: This node hits other limit, such as node limit, path limit.
## Queries
**Important**: These diagramming features use the `/query` endpoint, not
`/search`. If you type this syntax in the regular search box, it won't work.
### Inheritance diagram
```
inheritance-diagram:'nsIInputStream' depth:4
```
### Class diagram
```
class-diagram:'mozilla::GraphDriver' depth:3
```
### Function call diagram
This works both directions.
```
calls-from:'mozilla::dom::AudioContext::CreateDynamicsCompressor' depth:2
calls-to:'mozilla::dom::AudioContext::CreateDynamicsCompressor' depth:4
```
**Note**: `calls-from` now avoids traversing into methods like
`NS_DebugBreak` that would otherwise clutter diagrams. Similarly, `calls-to`
and `calls-between` avoid problematic interfaces like `nsIObserver::Observe`
and `nsISupports` methods.
## Calls Between
The `calls-between` functionality allows you to discover how different classes
or methods interact with each other. This is particularly useful for
understanding complex code relationships.
This functionality is not yet available in the context menu.
### Basic calls-between
Find paths between any methods of two classes:
```
calls-between:'mozilla::ProcessPriorityManager' calls-between:'nsTimer'
```
### Directional calls-between
For more precise control, use `calls-between-source` and `calls-between-target`:
```
calls-between-source:'nsDocShell' calls-between-target:'nsExternalHelperAppService' depth:10
```
### Specific method targeting
When you know specific methods, you can target them directly:
```
calls-between-source:'nsGlobalWindowInner::SetTimeout' calls-between-source:'nsGlobalWindowInner::ClearTimeout' calls-between-target:'nsTimer' depth:9
```
**Note**: You must now provide absolute pretty identifiers. If your class is
`foo::Bar`, you can't just use `Bar` - you need the full path to avoid
ambiguity.
### Include Graph Visualization
There's a synthetic "(file symbol)" at the end of file path breadcrumbs.
Diagrams triggered on this symbol visualize the header include file graph. This
is most useful with `calls-between` queries.
### Advanced Options
- `fmus-through-depth:N` - Include "field member uses" for pointer relationships (use 0 for depth 0 nodes only)