Go String Highlighter

Go String Highlighter

Adds syntax highlighting inside Go string literals when you tag them with a comment marker on the line above.

It only affects the string contents; the surrounding Go code stays highlighted normally.

Rules (kept intentionally simple):

• Applies only to Go files (source.go).
• Only the first string literal on the next line after the marker is injected.
• If the next line has no string literal, nothing happens.

Usage

Add a standalone line comment (case-insensitive) immediately above a line that contains a Go string literal:

// sql
query := "SELECT * FROM users;"

// regexp
_, _ = regexp.MatchString(`(?i)^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,}$`, "")

// javascript
js := `function greet(name) {
  return "Hi " + name;
}`

// For compatibility with JetBrains IDEs, `// language=<tag>` is also accepted:
// language=postgres
q := `SELECT now() RETURNING 1;`

See example.go for a bunch of copy-pasteable examples across all supported tags.

Install

VS Code Marketplace

Search for Go String Highlighter in VS Code Extensions and click Install.

Local (VSIX)

If you want to install a .vsix locally:

1. Build one with vsce package.
2. Install it:
   • VS Code: “Extensions” → “⋯” → “Install from VSIX…”
   • Or CLI: code --install-extension go-string-highlighter-*.vsix
3. Reload VS Code.

Supported Tags

SQL (generic + dialects)

• Generic: sql, ddl, dml
• PostgreSQL: postgres, postgresql, pgsql
• PL/pgSQL: plpgsql, pl/pgsql
• MySQL / MariaDB: mysql, mariadb
• SQLite: sqlite
• SQL Server (T-SQL): tsql, mssql
• Oracle (PL/SQL): plsql, oracle
• BigQuery: bigquery

Config / IaC

• toml
• hcl, hcl2
• terraform, tf
• nomad
• cue
• jsonnet

APIs / schemas

• proto, protobuf, proto2, proto3
• graphql, gql

Policy / auth

• rego, opa
• cel

Observability

• promql

Templates

• Go templates: gotmpl, go-template, gotemplate, tmpl, tpl
• templ
• jinja, jinja2, j2

Data / config

• json, jsonc, json5, jsonl, jsonlines
• yaml, yml
• ini, conf
• xml

Web / templating

• html, htm, xhtml
• css, scss, less
• js, javascript, jsx, mjs, cjs
• ts, typescript, tsx

Shell / ops

• sh, bash, zsh, shell, fish
• dockerfile, Dockerfile

Scripting

• lua
• py, python
• rb, ruby

Docs / misc

• md, markdown
• regexp, regex, re

Known broken examples

Some languages still break Go highlighting because their grammars can stay in an “open” state and swallow the Go delimiter. Their example.go entries are commented out until a safer injection can be found:

• toml, cue, jsonnet, graphql, gql, rego, opa, cel, promql

Dialect Notes

Dialect-specific highlighting depends on having a VS Code extension installed that contributes a matching TextMate grammar.

• For postgres|postgresql|pgsql: if you have ms-ossdata.vscode-pgsql installed, this extension uses its pgsql.injection grammar to add Postgres keywords (e.g. RETURNING, ON CONFLICT) on top of generic SQL.
• For other dialects: this extension tries common scope names (e.g. source.sql.mysql, source.sql.tsql) and falls back to generic source.sql if no dialect grammar is available.

Troubleshooting

• Use “Developer: Inspect Editor Tokens and Scopes” inside the annotated string to confirm the injected scopes.
• If a dialect keyword isn’t highlighted, you likely don’t have a dialect grammar installed (or its scopeName doesn’t match what this extension tries); in that case it will correctly fall back to generic SQL.

About

MIT Licensed. See LICENSE.

Created by Gurpartap Singh.