Remove compatibility checks for levelup & friends

UPGRADING.md

@@ -47,6 +47,8 @@ _This is a work in progress upgrade guide for the upcoming 2.0.0 release._
 
 The guide for this release consists of two sections. One for the public API, relevant to all consumers of `abstract-level` and implementations thereof (`level`, `classic-level`, `memory-level` et cetera) and another for the private API that only implementors should have to read.
 
+If you're upgrading from `levelup`, `abstract-leveldown` or other old modules, it's recommended to first upgrade to `abstract-level` 1.x because that version includes compatibility checks that have since been removed.
+
 ### 1. Public API
 
 #### 1.1. Callbacks have been removed

abstract-iterator.js

@@ -405,14 +405,6 @@ class IteratorDecodeError extends ModuleError {
 //   }
 // }
 
-// To help migrating to abstract-level
-for (const k of ['_ended property', '_nexting property', '_end method']) {
-  Object.defineProperty(AbstractIterator.prototype, k.split(' ')[0], {
-    get () { throw new ModuleError(`The ${k} has been removed`, { code: 'LEVEL_LEGACY' }) },
-    set () { throw new ModuleError(`The ${k} has been removed`, { code: 'LEVEL_LEGACY' }) }
-  })
-}
-
 function assertStatus (iterator) {
   if (iterator[kClosing]) {
     throw new ModuleError('Iterator is not open: cannot read after close()', {

lib/abstract-sublevel.js

@@ -23,17 +23,6 @@ const defaults = { separator: '!' }
 module.exports = function ({ AbstractLevel }) {
   class AbstractSublevel extends AbstractLevel {
     static defaults (options) {
-      // To help migrating from subleveldown to abstract-level
-      if (typeof options === 'string') {
-        throw new ModuleError('The subleveldown string shorthand for { separator } has been removed', {
-          code: 'LEVEL_LEGACY'
-        })
-      } else if (options && options.open) {
-        throw new ModuleError('The subleveldown open option has been removed', {
-          code: 'LEVEL_LEGACY'
-        })
-      }
-
       if (options == null) {
         return defaults
       } else if (!options.separator) {

lib/range-options.js

@@ -1,6 +1,5 @@
 'use strict'
 
-const ModuleError = require('module-error')
 const hasOwnProperty = Object.prototype.hasOwnProperty
 const rangeOptions = new Set(['lt', 'lte', 'gt', 'gte'])
 
@@ -11,17 +10,6 @@ module.exports = function (options, keyEncoding) {
     if (!hasOwnProperty.call(options, k)) continue
     if (k === 'keyEncoding' || k === 'valueEncoding') continue
 
-    if (k === 'start' || k === 'end') {
-      throw new ModuleError(`The legacy range option '${k}' has been removed`, {
-        code: 'LEVEL_LEGACY'
-      })
-    } else if (k === 'encoding') {
-      // To help migrating to abstract-level
-      throw new ModuleError("The levelup-style 'encoding' alias has been removed, use 'valueEncoding' instead", {
-        code: 'LEVEL_LEGACY'
-      })
-    }
-
     if (rangeOptions.has(k)) {
       // Note that we don't reject nullish and empty options here. While
       // those types are invalid as keys, they are valid as range options.

test/clear-test.js

@@ -3,29 +3,6 @@
 const isBuffer = require('is-buffer')
 const { Buffer } = require('buffer')
 
-exports.args = function (test, testCommon) {
-  test('clear() with legacy range options', async function (t) {
-    t.plan(2)
-
-    const db = testCommon.factory()
-    await db.open()
-
-    try {
-      await db.clear({ start: 'foo' })
-    } catch (err) {
-      t.is(err.code, 'LEVEL_LEGACY')
-    }
-
-    try {
-      await db.clear({ end: 'foo' })
-    } catch (err) {
-      t.is(err.code, 'LEVEL_LEGACY')
-    }
-
-    return db.close()
-  })
-}
-
 exports.clear = function (test, testCommon) {
   makeTest('string', ['a', 'b'])
 
@@ -128,7 +105,6 @@ exports.events = function (test, testCommon) {
 }
 
 exports.all = function (test, testCommon) {
-  exports.args(test, testCommon)
   exports.events(test, testCommon)
   exports.clear(test, testCommon)
 }

test/self.js

@@ -777,7 +777,7 @@ test('rangeOptions', function (t) {
     t.end()
   }
 
-  t.plan(11)
+  t.plan(10)
   t.test('setup', async (t) => db.open())
 
   t.test('default options', function (t) {
@@ -859,21 +859,6 @@ test('rangeOptions', function (t) {
     })
     verifyOptions(t, getRangeOptions(options, db.keyEncoding('utf8')))
   })
-
-  t.test('rejects legacy range and encoding options', function (t) {
-    t.plan(3)
-
-    for (const key of ['start', 'end', 'encoding']) {
-      const options = {}
-      options[key] = 'x'
-
-      try {
-        getRangeOptions(options, db.keyEncoding('utf8'))
-      } catch (err) {
-        t.is(err.code, 'LEVEL_LEGACY')
-      }
-    }
-  })
 })
 
 require('./self/abort-test')

test/self/abstract-iterator-test.js

@@ -189,26 +189,3 @@ for (const Ctor of [AbstractIterator, AbstractKeyIterator, AbstractValueIterator
     await db.close()
   })
 }
-
-test('AbstractIterator throws when accessing legacy properties', async function (t) {
-  t.plan(3 * 2)
-
-  const db = testCommon.factory()
-  await db.open()
-  const it = new AbstractIterator(db, {})
-
-  for (const k of ['_ended property', '_nexting property', '_end method']) {
-    try {
-      // eslint-disable-next-line no-unused-expressions
-      it[k.split(' ')[0]]
-    } catch (err) {
-      t.is(err.code, 'LEVEL_LEGACY')
-    }
-
-    try {
-      it[k.split(' ')[0]] = 123
-    } catch (err) {
-      t.is(err.code, 'LEVEL_LEGACY')
-    }
-  }
-})

test/self/sublevel-test.js

@@ -161,12 +161,6 @@ test('sublevel prefix and options', function (t) {
     t.end()
   })
 
-  t.test('legacy sublevel(down) options', function (t) {
-    t.throws(() => new NoopLevel().sublevel('foo', 'bar'), (err) => err.code === 'LEVEL_LEGACY')
-    t.throws(() => new NoopLevel().sublevel('foo', { open: () => {} }), (err) => err.code === 'LEVEL_LEGACY')
-    t.end()
-  })
-
   // See https://github.com/Level/subleveldown/issues/78
   t.test('doubly nested sublevel has correct prefix', async function (t) {
     t.plan(1)