[claude]

Draft until #884 lands — nothing for you to do. This branch carries #884's head merged in (one import line in src/parser.ts conflicted; both branches touch that file), so merging this before #884 would land #884's change with it.

Output change, for boolean root schemas only: a schema file that is nothing but true or false now compiles to a named type instead of an empty file. Every other schema's output is byte-identical (checked below).

What changes for you

From draft 6 on, a JSON Schema document may be a bare boolean: true accepts every value, false accepts none. This compiler emitted nothing but the banner comment for such a file, because the root had no keyword to be named by and so was never declared. With unreachableDefinitions on, or through compileFiles, it crashed (Cannot read properties of undefined (reading 'has')).

Now the root is declared under the file's name, the same rule an object root without an $id already follows, and compile() accepts a boolean:

Input	Before	After
Anything.json containing true	banner comment only	export type Anything = unknown;
Nothing.json containing false	banner comment only	export type Nothing = never;
compile(true, 'Root')	banner comment only	export type Root = unknown;
compile(false, 'Root')	banner comment only	export type Root = never;
echo true | json2ts (stdin)	banner comment only	export type NoName = unknown;
compile(true, 'Root', {unreachableDefinitions: true}), compileFiles with a boolean member	crash	the type above

The library, the CLI (file, stdin, YAML, directory, --imports), compileFromFile and compileFiles all go through the same path. --no-unknownAny gives any, as for every other true schema. The customName option is not consulted for a boolean root, since that function is handed schema objects; the file name is the name.

How

• parseRoot (src/parser.ts): a boolean root gets parseBooleanSchema's node plus a standalone name; an object root goes to parse as before. parseUnreachableDefinitions returns nothing for a boolean root instead of reading its (absent) type set.
• rootNameFromFile (src/utils.ts): the one rule for a root without a name of its own (toSafeString(justName(file)) || 'NoName'), now shared by the normalizer's $id rule and the parser.
• compile()'s schema parameter accepts boolean. Nothing else in the public API changes.
• README: the draft 6 boolean-schema row no longer says a root true/false errors (and no longer says a $ref to one crashes, which Fix crash on $ref to a boolean schema or other non-object value (#725) #809 fixed).

Tests

• New e2e cases booleanSchemaRoot.true.ts and booleanSchemaRoot.false.ts (two snapshot entries, placed beside refToBooleanSchema.ts; no existing entry changes).
• compileFromFile test with test/resources/BooleanRoot/{Anything,Nothing}.json, asserting the full output including the banner; two CLI tests (file, stdin).
• All five new tests fail on master 5caacfc and pass here. Suite: CI=true bun run test 687 pass / 0 fail at fef9931 (master: 680 / 0); 691 / 0 at 7ff419a (with Name an array's enum items after the array (RolesItems) instead of leaking the KeyNameFromDefinitionItems placeholder #884's four).
• bun run corpus: 26 schemas × 3 option sets compile and type-check; the 78 outputs (--e2e --out) are byte-identical to master's at fef9931, and at 7ff419a byte-identical to Name an array's enum items after the array (RolesItems) instead of leaking the KeyNameFromDefinitionItems placeholder #884's own head's (the only differences from master are Name an array's enum items after the array (RolesItems) instead of leaking the KeyNameFromDefinitionItems placeholder #884's disclosed renames).

Conformance baseline

bun run conformance on master reports the eight boolean_schema.json groups (drafts 6, 7, 2019-09, 2020-12; true and false each) as invalid-output (no Root declaration). They now score perfectly, so test/conformance/baseline.json is re-recorded (node test/conformance/run.js --update): the eight group lines change from "invalid-output" to [0,9,0,0] (true: 0 of 9 valid instances rejected) and [0,0,0,9] (false: 0 of 9 invalid instances accepted), and the totals move accordingly (invalid-output 8 → 0, valid instances 5262 → 5298, invalid instances 3606 → 3642). No other line moves; the harness exits 0 on this head.

Merge check

git merge-tree --write-tree of fef9931 against each open draft: clean against #879, #880, #881, #882, #883, #885, #886; conflicts with #884 on the import … from './utils' line of src/parser.ts (#884 adds hasType, this adds rootNameFromFile). Resolved by merging #884's head 9488e4f into this branch (7ff419a, import line takes both names, nothing else hand-edited): snapshot interdiff against master is exactly this PR's two entries plus #884's own diff, suite and conformance green. So this lands after #884; once #884 is on master the merge commit is a no-op.

Changelog

• A boolean root schema (true / false) compiles to export type X = unknown / never instead of an empty file (and no longer crashes with unreachableDefinitions or compileFiles).