Plugins and rule set

Decides which rules the run has, and the severity each one runs at. It works from the built-in plugins and the plugins the config lists, and it runs before any form is read.

A plugin is an object with a name, a version and its rules. It can also declare the runtime versions it checks against (compat), and a hostVariables hook that supplies names to Name analysis, such as the Smart Forms sourceQueries names. The name is the namespace of its rules' IDs: the smart-forms plugin's rule unsupported-query-embedding is smart-forms/unsupported-query-embedding. Core has two built-in plugins: sdc, with the core rules, and lint, which holds only lint/stale-suppression. Both names are reserved. Installing a plugin's package does not enable it; listing it in plugins in an .mjs config does.

resolveRuleSet builds the rule set in four steps:

1. It checks each listed plugin against the plugin contract, and rejects a reserved namespace or one already registered. A rule's docsUrl must be an absolute URL; it is copied into each of the rule's findings.
2. It picks the runtime versions for each plugin that declares compat: the newest verified ones by default (latest), or the exact verified versions the config names.
3. It gives each rule its setting: the one in the config's rules, or else the rule's default severity. off keeps the rule from running.
4. It checks every rule ID that rules and suppress name, and suggests a similar ID when one is unknown. lint/stale-suppression can only be warning or off, and lint/ findings cannot be suppressed.

A problem at any step stops the run with CONFIG_INVALID. lint and explain build the same rule set, so they fail the same way.

Plugins shows how to list one, Adding a rule how to write one, and What a plugin can import the API core gives plugins.

Schema

The RuleSet holds every rule sorted by ID, including those set to off, each with its setting and its compat versions. It also holds the plugin versions and the selected compat for the report, and the plugins' hostVariables hooks, in config order, for Name analysis.

Code

In packages/core/src/plugins/:

• rule-set.ts: resolveRuleSet builds the rule set as above. unknownRuleHelp suggests a similar rule ID, for the config and for explain.
• contract.ts: the plugin contract, public API: LintPlugin, LintRule, RuleContext, RuleFinding, RuleDocs, PluginCompat and HostVariablesInput.
• builtin.ts: the sdc and lint plugins. It also says where each built-in rule completes its check, which Suppressions uses to find stale entries and the summary uses to count unchecked expressions.
• core-rule.ts: CoreRule, an sdc rule that also receives core's analysis of the form. Plugin rules get only the public RuleContext.