Some nasty loot context stuff written in TypeScript in case someone wants it

Loot Context.ts

const enum LootContext {
  BlockEntity,
  BlockState,
  DamageSource,
  DirectKillerEntity,
  ExplosionRadius,
  KillerEntity,
  LastDamagePlayer,
  Origin,
  ThisEntity,
  Tool
}

type LootContextRegistration = { requires: LootContext[], allows: LootContext[] }

const LootContextTypes = new Map<string, LootContextRegistration>([
  ['minecraft:advancement_entity', { requires: [LootContext.Origin, LootContext.ThisEntity], allows: [] }],
  ['minecraft:advancement_reward', { requires: [LootContext.Origin, LootContext.ThisEntity], allows: [] }],
  ['minecraft:barter', { requires: [LootContext.ThisEntity], allows: [] }],
  ['minecraft:chest', { requires: [LootContext.Origin], allows: [LootContext.ThisEntity] }],
  ['minecraft:command', { requires: [LootContext.Origin], allows: [LootContext.ThisEntity] }],
  ['minecraft:empty', { requires: [], allows: [] }],
  ['minecraft:entity', { requires: [LootContext.DamageSource, LootContext.Origin, LootContext.ThisEntity], allows: [LootContext.DirectKillerEntity, LootContext.KillerEntity, LootContext.LastDamagePlayer] }],
  ['minecraft:fishing', { requires: [LootContext.Origin, LootContext.Tool], allows: [LootContext.ThisEntity] }],
  ['minecraft:gift', { requires: [LootContext.Origin, LootContext.ThisEntity], allows: [] }],
  ['minecraft:selector', { requires: [LootContext.Origin], allows: [LootContext.ThisEntity] }],
  ['minecraft:generic', { requires: [LootContext.DamageSource, LootContext.BlockEntity, LootContext.BlockState, LootContext.DirectKillerEntity, LootContext.ExplosionRadius, LootContext.KillerEntity, LootContext.LastDamagePlayer, LootContext.Origin, LootContext.ThisEntity, LootContext.Tool], allows: [] }],
  ['minecraft:block', { requires: [LootContext.BlockState, LootContext.Origin, LootContext.Tool], allows: [LootContext.BlockEntity, LootContext.ExplosionRadius, LootContext.ThisEntity] }]
])

/**
 * A map from loot entity sources to an array of their required context.
 */
const LootEntitySources = new Map<string, LootContext[]>([
  ['direct_killer', [LootContext.DirectKillerEntity]],
  ['killer', [LootContext.KillerEntity]],
  ['killer_player', [LootContext.KillerEntity]],
  ['this', [LootContext.ThisEntity]]
])

/**
 * A map from loot copy sources to an array of their required context.
 */
const LootCopySources = new Map<string, LootContext[]>([
  ['block_entity', [LootContext.BlockEntity]],
  ['direct_killer', [LootContext.DirectKillerEntity]],
  ['killer', [LootContext.KillerEntity]],
  ['killer_player', [LootContext.KillerEntity]],
  ['this', [LootContext.ThisEntity]]
])

/**
 * A map from loot condition IDs to an array of their required context.
 */
const LootConditions = new Map<string, LootContext[]>([
  ['minecraft:alternative', []],
  ['minecraft:block_state_property', [LootContext.BlockState]],
  ['minecraft:damage_source_properties', [LootContext.DamageSource]],
  ['minecraft:entity_properties', [LootContext.Origin]],
  ['minecraft:entity_scores', []],
  ['minecraft:inverted', []],
  ['minecraft:killed_by_player', [LootContext.LastDamagePlayer]],
  ['minecraft:location_check', []],
  ['minecraft:match_tool', [LootContext.Tool]],
  ['minecraft:random_chance', []],
  ['minecraft:random_chance_with_looting', [LootContext.KillerEntity]],
  ['minecraft:reference', []],
  ['minecraft:survives_explosion', [LootContext.ExplosionRadius]],
  ['minecraft:table_bonus', [LootContext.Tool]],
  ['minecraft:time_check', []],
  ['minecraft:weather_check', []]
])

/**
 * A map from loot function IDs to an array of their required context.
 */
const LootFunctions = new Map<string, LootContext[]>([
  ['minecraft:apply_bonus', [LootContext.Tool]],
  ['minecraft:copy_name', []],
  ['minecraft:copy_nbt', []],
  ['minecraft:copy_state', [LootContext.BlockState]],
  ['minecraft:enchant_randomly', []],
  ['minecraft:enchant_with_levels', []],
  ['minecraft:exploration_map', [LootContext.Origin]],
  ['minecraft:explosion_decay', []],
  ['minecraft:fill_player_head', []],
  ['minecraft:furnace_smelt', []],
  ['minecraft:limit_count', []],
  ['minecraft:looting_enchant', [LootContext.KillerEntity]],
  ['minecraft:set_attributes', []],
  ['minecraft:set_contents', []],
  ['minecraft:set_count', []],
  ['minecraft:set_damage', []],
  ['minecraft:set_loot_table', []],
  ['minecraft:set_lore', []],
  ['minecraft:set_name', []],
  ['minecraft:set_nbt', []],
  ['minecraft:set_stew_effect', []]
])

An updated one can be found here (permalink).