vscode-mermaid-syntax-highlight

Syntax support for the Mermaid charting language

Supports both fenced markdown (see screenshots), and mmd files.

Screenshots/Progress

Graph

graph TB %% comments
  %% Entity[Text]
  ID-1[Node 1]
  ID-2>Node 2]
  ID-3(Node 3 <br> text)
  %% Entity--Entity
  ID-1---ID-2
  ID-1 --> ID-3
  %% Entity--Text--Entity
  ID-2--Link between 2 and 3---ID-3
  ID-3-->|Action from 3 to 1|ID-1
  ID-3 -- "Action from 3 to 2. p/w: '_-!#$%^&*+=?,\'" --> ID-2
  %% Complex cases
  A[Hard edge] -->|Link text| B(Round edge)
  ID-1---ID-2(Text)
  B --> C{Text}
  C -->|One| D[Text]
  %% class/classDef
  classDef blue fill:#08f,stroke:#fff;
  class ID-1 blue
  class ID-1,ID-2 red
  %% click
  click ID-1 "https://github.com" "Tooltip text" %% comments
  click ID-2 alert "Tooltip for a callback"
  %% subgraph
  subgraph A subgraph
    ID-4{Node 4}
    ID-5((fa:fa-spinner))
    ID-6["Node 6 (same #quot;shape#quot;)"]
    ID-4-.->ID-5
    ID-5 -. Action from 5 to 4 .-> ID-4
    ID-5==>ID-6
    ID-6 == Action from 6 to 5 ==> ID-5
  end

Progress

[x] Keywords
[x] %% Comments
[x] Entity---Entity (livne )
[x] Entity---Text---Entity
[x] Entity-->|Text|Entity
[x] Entity-->|Special Chars|Entity
[x] Entity[Text]
[x] classDef
[x] class
[x] click

Sequence

sequenceDiagram %% diagram
  %% participant
  participant Alice
  participant B as Bob
  participant C as Carol
  %% arrows
  B->C: Solid line without arrow
  B-->C: Dotted line without arrow
  B->>C:Solid line with arrowhead
  B-->>C: Dotted line with arrowhead
  B-xC: Solid line with a cross at end
  B--xC: Dotted line with a cross at end
  %% activations
  activate John
  deactivate John
  %% activation shorthand
  Bob->>+Carol: Hello Carol, how are you?
  B-->>-C: Great!
  %% notes
  Note left of Alice: Alice likes to chat
  Note over B,C: Bob whispers when sick
  %% loop
  loop Every minute
        B-->C: Can you hear me?
  end
  %% alt
  alt is sick
    B-->C: Not so good :(
  else is well
    B->C: Feeling fresh like a daisy
  end
  opt Extra response
    B->C: You, Carol?
  end

[x] Keywords
[x] %% Comments
[x] participant Actor
[x] participant Aliases
[x] Actor->>Actor: Message
[x] 6 arrow types
[x] (de)activate Actor
[x] activate/deactivate shorthand (+/-)
[x] Note Action Actor
[x] Multi-actor notes
[x] loop
[x] alt
[x] alt optional

Gantt

gantt %%comment
  dateFormat  YYYY-MM-DD
  axisFormat  %m/%d/%Y
  title Adding GANTT diagram functionality to mermaid
  section A section %%comment
  Completed task            :done,    des1, 2014-01-06,2014-01-08
  Active task               :active,  des2, 2014-01-09, 3d
  Future task               :         des3, after des2, 5d %%comment
  Future task2               :         des4, after des3, 5d
  A task           :a1, 2014-01-01, 30d
  section Critical tasks
  Completed task in the critical line :crit, done, 2014-01-06,24h
  Implement parser and jison          :crit, done, after des1, 2d
  Create tests for parser             :crit, active, 3d
  Future task in critical line        :crit, 5d
  Create tests for renderer           :2d
  Add to mermaid                      :1d

[x] Keywords
[x] %% Comments
[x] dateFormat
[x] axisFormat
[x] title
[x] section
[x] task

Initial Idea

Based on the starter language support repo here, and initially created based on the Atom language support here.

TODO

[x] Graph support
[x] Sequence Diagram support
[x] Gantt support
[x] Support highlighting in mmd files.

Building

The grammar resides in the syntaxes/mermaid.tmLanguage.yaml file. Only make changes to this file. The json version is required for the extension and is generated. To generate the json file run:

npm run convertYaml

To test the theme locally, uninstall the theme from the marketplace and clone this repository directly into the vscode extensions folder. Any changes can be seen after running the Reload Window command in vs code.

Developing

The grammar includes a custom yaml type regex. This should be used for all but the simplest regex expressions. It was created to allow the regex to be multiline (with no whitespace between lines) and in-line comments that are stripped from the json. To use it, prepend !regex as seen below:

reg: !regex |-
  # Comment
  \s*(class)\s+ # explanation
  (\b[-,\w]+)\s+ # comment

Becomes:

{
  "reg": "\\s*(class)\\s+(\\b[-,\\w]+)\\s+"
}

Instead of:

{
  "reg": "# Comment\n\\s*(class)\\s+ # explanation\n(\\b[-,\\w]+)\\s+ # comment"
}

This is useful for splitting out sections of the regex (such as capture groups) and commenting on what each group should be matching.

Mermaid Markdown Syntax Highlighting

Brian Pruitt-Goddard