Two API fields carry restricted emoji-value sets that the scraper's
curly-quote regex strips during IR extraction (multi-byte boundary
issue): ReactionTypeEmoji.Emoji and sendDice.Emoji. They previously
typed as plain string with no compile-time guarantee on values.
Add hand-curated typed-string enums in api/enums.go (the manual file,
not enums.gen.go):
- DiceEmoji: 6 constants (Dice, Dart, Basketball, Football, Bowling,
SlotMachine) covering Telegram's full set for sendDice.
- ReactionEmoji: 73 constants covering the canonical reaction set
from https://core.telegram.org/bots/api#reactiontypeemoji. Names
follow Unicode CLDR short names where one exists, otherwise stable
common-English labels (e.g. ThumbsUp, Heart, Clown, ManTechnologist).
Wire the field-type override via cmd/genapi/emitter.go:
- fieldTypeOverrides map keyed "<TypeOrParamsName>.<FieldName>".
- goField/multipartFieldEntry consult the override after the enum-plan
lookup; falls through to the default goType when nothing matches.
- methods.tmpl gains goFieldP/multipartFieldEntryP helpers that pass
the params type name as override-parent (the params struct doesn't
share a Go type with the field, so the existing parent="" enum-key
convention is preserved).
Regenerated api/types.gen.go and api/methods.gen.go now type the two
fields as ReactionEmoji and DiceEmoji respectively. No other Emoji
field is affected (override is scoped per parent type). regen-from-
fixture is byte-deterministic across runs.
Add api/emoji_enums_test.go covering const wire values, reflection
checks on field types, and a marshal/unmarshal round-trip for
ReactionTypeEmoji.
Sealed-interface union variants whose Type/Source field is declared as
bare prose (e.g. "Type of the result, must be article" or "Scope type,
must be all_private_chats") were skipped by extractEnumValues because
the existing patterns require curly-quoted values. The genapi emitter
already extracted these values via discBareRE for marshal-side
discriminator injection; lifting the same detection into the scraper
populates Field.EnumValues so planUnifiedUnionEnums folds them into
shared union-level enums automatically.
Unions newly unified (10): BotCommandScope, MenuButton, InputMedia,
InputPaidMedia, InputPollMedia, InputPollOptionMedia, InputProfilePhoto,
InputStoryContent, InlineQueryResult, PassportElementError.
InputMessageContent stays excluded — its variants dispatch
structurally on field presence and have no Type/Source field, so
planUnifiedUnionEnums correctly skips it.
Constants added: 60 typed enum constants across the 10 unions; the
corresponding variant struct fields are retyped from string to the
shared enum.
Internal call-site cleanups: 0 — no internal package referenced these
discriminator values via magic strings.
False positives the prose detector explicitly rejects: terminal
prose-word continuations like "must be sent", "must be shown above",
"must be specified", "must be paid", "must be active", "must be one
of 3, 6, or 12", "must be between 5 and 100000", "must be a Pay
button", "must be repainted". Guarded via terminal-position regex
anchor + closed-list isProseWord filter.
Determinism verified across two consecutive make regen-from-fixture
runs. go test -race ./..., go vet ./..., staticcheck ./... all clean.
Each sealed-interface union with N variants used to emit N typed-string
enums, one per variant, each holding exactly one wire value. Codegen now
detects this pattern and emits ONE unified enum at the union level,
retyping every variant's discriminator field to point at it.
Unified enums (11 unions, 44 constants total):
- ChatMemberStatus (6)
- MessageOriginType (4)
- BackgroundFillType (3)
- BackgroundTypeKind (4)
- ChatBoostSourceKind (3)
- OwnedGiftType (2)
- PaidMediaType (4)
- ReactionTypeKind (3)
- RevenueWithdrawalStateKind (3)
- StoryAreaTypeKind (5)
- TransactionPartnerType (7)
Naming-collision cases (union name already ends in a discriminator
concept noun, so the natural concat would stutter): BackgroundType,
ReactionType, StoryAreaType, ChatBoostSource, RevenueWithdrawalState.
The unified name ends with 'Kind' instead.
44 obsolete per-variant single-value enum types removed (e.g.
ChatMemberOwnerStatus, MessageOriginUserType). The variant struct types
themselves (ChatMemberOwner etc.) are unchanged; only their per-variant
single-value enum aliases go away.
Auto-inject MarshalJSON (commit 370c9c0) is unaffected — variant wire
values still come from the discriminator-extractor pass.
Call-site cleanup:
- dispatch/filters/chatmember/chatmember_test.go
- api/marshaljson_variants_test.go
New test: api/unifiedenum_test.go covers ChatMemberStatus and
MessageOriginType: variant-field retype, direct comparison without
conversion, marshal discriminator preservation, full round-trip,
stutter-suffix Kind sanity check.
Sealed-interface union variants now hardcode their wire discriminator
inside a generated MarshalJSON method instead of forcing callers to set
the field on every struct literal. Drops a class of silent-rejection
bugs where a typo in the discriminator slipped past the type checker
and through to Telegram, which then rejected the request with no
Go-side signal.
The discriminator field stays exported so incoming-message decoding,
type switches and debugging still see it. MarshalJSON wraps via a
function-local type alias and emits an outer field with the same json
tag; encoding/json (and goccy/go-json) resolve the outer field as the
shallower one and override whatever the caller wrote.
99 variants get MarshalJSON. 7 are skipped because their unions
dispatch structurally rather than by a string field: Message and
InaccessibleMessage (MaybeInaccessibleMessage, dispatched on date),
and the InputMessageContent family (InputTextMessageContent,
InputLocationMessageContent, InputVenueMessageContent,
InputContactMessageContent, InputInvoiceMessageContent — Telegram
identifies these by the presence of message_text / latitude /
phone_number / title etc.).
Discriminator extraction lives in the emitter (cmd/genapi/emitter.go).
Resolution: knownDiscriminators reverse-lookup for the 13 auto-decode
unions, then doc-string analysis ("must be X" / "always “X”")
of the variant's first required string field for marker-only unions
(BotCommandScope, InputMedia, InputPaidMedia, InputProfilePhoto,
InputStoryContent, InputPollMedia, InputPollOptionMedia,
InlineQueryResult, PassportElementError). Variants the emitter cannot
resolve a discriminator for are skipped silently rather than emitting
broken code.
Internal call-site cleanups: 4 manual discriminator assignments
removed (api/unionparam_test.go,
dispatch/filters/message/message_test.go, examples/inline/main.go ×2).
Regression tests added in api/marshaljson_variants_test.go covering
type-keyed variants, source-keyed variants, the override-user-typo
guarantee, round-trip preservation through UnmarshalChatMember, the
no-discriminator InputMessageContent path, and ride-along of
non-discriminator fields.
regen-from-fixture is deterministic across two consecutive runs;
go test -race / go vet / staticcheck all clean.
Optional fields whose type was a sealed-interface union without an
auto-decode discriminator (BotCommandScope, InputMedia, InputPaidMedia,
InputProfilePhoto, InputStoryContent, InputMessageContent,
InputPollMedia, InputPollOptionMedia, InlineQueryResult,
PassportElementError) were emitted as *<Union> — pointer to interface,
which is a Go anti-pattern: interfaces are already nil-able, and
callers were forced to take addresses of concrete variants.
The codegen path goType() guarded against pointer-wrapping using
knownDiscriminators (only 13 unions with auto-decode dispatch), missing
the 10 marker-only sealed interfaces. New package var
knownInterfaceTypes is built from buildUnionTypeSet at emitter
construction and covers both kinds. goType() now consults that.
Net effect:
- api/methods.gen.go: 3 *BotCommandScope and 2 *InputPollMedia fields
become bare interface
- api/types.gen.go: 14 *InputMessageContent and 1 *InputPollOptionMedia
fields become bare interface
Regression tests in api/unionparam_test.go cover both shapes:
direct concrete-variant assignment, and nil omitempty on the bare
interface field.
GetChatAdministrators returns []ChatMember, where ChatMember is a
sealed-interface union. The codegen template emitted the generic
client.Call[..., []ChatMember] for it — encoding/json cannot unmarshal
a slice of an interface (no discriminator-aware path), so every real
response from Telegram failed at the parse step:
telegram: parse: json: cannot unmarshal api.ChatMember into
Go struct field Result[[]ChatMember].Result of type api.ChatMember
Fix is in cmd/genapi/methods.tmpl: add a third branch alongside the
existing single-union branch. When a method returns []<union>,
emit CallRaw + json.Unmarshal into []json.RawMessage + per-element
Unmarshal<Union>(e). Mirrors what GetChatMember (single-element)
already does, applied uniformly so any future slice-of-union method
Telegram introduces inherits the right shape.
Survey of v1.1.1 across all 23 sealed-interface unions confirms
GetChatAdministrators was the only broken site; the fix regenerates
just that one method body. New regression tests in
api/getchatadministrators_test.go cover the typical
admin+owner response and the empty-array case.
Telegram's optional int/bool/float fields are pointers so callers can
explicitly send false or 0 to override a chat default — distinct from
'absent', which uses the chat default. The pointer construction has been
ergonomically painful:
photoLimit := int64(5)
Limit: &photoLimit
api.Ptr[T any](v T) *T collapses that to a single line:
Limit: api.Ptr[int64](5)
DisableNotification: api.Ptr(true)
Pointers stay because the explicit-zero distinction matters for fields
like DisableNotification, ProtectContent, and getUpdates.Offset where
sending 0 / false explicitly is semantically different from omitting
the field.
The Telegram docs describe many string fields and parameters with
phrases like "can be ..., or ...", "must be one of ...", or "always X",
yet the generated Go API surface used raw `string` for every one of
them. Callers had to write magic strings or `string(api.ChatTypePrivate)`
to satisfy the field type. This change makes those fields typed Go
string enums emitted from the IR, so the IDE autocompletes valid values
and breaking-value drift surfaces at compile time.
Pipeline changes:
- internal/spec/ir.go: Field gains EnumValues []string. Empty for non-
enum fields; otherwise the wire-level values in doc order, deduped.
- cmd/scrape/enums.go: extractEnumValues recognises the curly-quoted
patterns Telegram uses ("can be either", "currently can be", "one
of", "must be", "always X") and rejects free-text quoted refs (e.g.
"Can be available only for X") via a tight gap check between the
trigger phrase and the first quoted value. parse_mode parameters
get the canonical Markdown / MarkdownV2 / HTML triple injected
because Telegram links to a separate formatting-options section
instead of listing values inline.
- cmd/genapi/enums.go: planEnums groups fields by sorted value-tuple,
picks a canonical Go enum name (most-common candidate, parent-
prefixed beats plain, shortest beats longer, alphabetical for
determinism), resolves cross-group name collisions by parent prefix.
- cmd/genapi/emitter.go + templates: goField rewrites the field type
to the planned enum name; multipartFieldEntry casts typed enum
values back to string when composing the wire map; enums.tmpl now
iterates the planned enums instead of hardcoding four hand-curated
ones; sentinelForField produces typed-constant test fixtures.
- api/enums.gen.go: regenerated from the live IR. 66 enum types, 155
constants. ParseMode, ChatType, MessageEntityType, ChatMember /
MessageOrigin / PaidMedia / Background / StoryAreaType / Reaction /
TransactionPartner / PassportElement variant Status & Type fields
are now typed.
- api/enums.go: hand-coded UpdateType (used by transport.LongPoller).
The Telegram docs do not enumerate Update payload kinds inline, so
the codegen pipeline cannot synthesise this enum.
- api/types.gen.go, api/methods.gen.go, api/methods_gen_test.go: 137
field declarations rewritten string -> typed enum.
- dispatch/, examples/: dropped every string(api.<Const>) cast. The
HasEntity filter now takes api.MessageEntityType; ChatType filter
compares typed values directly. ChatMember discriminator filter
casts variant.Status (typed per variant) to string for comparison.
- internal/spec/api.json, testdata/golden/*: regenerated and
refreshed. make regen-from-fixture is byte-deterministic across
runs.
Renames (no compat shims; v1 pre-public):
- EntityX -> MessageEntityTypeX (e.g. EntityBotCommand -> MessageEntityTypeBotCommand)
- EntityStrike -> MessageEntityTypeStrikethrough (full wire name)
- Add gomarkdoc-driven reference docs in docs/reference/, regenerated
automatically by 'make regen' alongside the api/ codegen
- New 'make docs' target installs gomarkdoc on first run; 'make
docs-check' is a CI gate
- Fold doc-clean assertion into existing codegen-clean job (single
diff check covers spec + api + reference)
- Rewrite README header: logo via <picture>, friendlier tagline,
emoji-led 'Why you'll like it' bullets instead of Why-table
- Drop duplicate echo snippet, soften 'Codegen pipeline' section into
'Keeping up with Telegram'
- Link reference from README, Pages nav, and a new Markdown reference
card on index.html (target = GitHub source view, renders .md natively)
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