api: api_info()['version']

API level is disconnected from NVIM version. The API metadata holds the
current API level, and the lowest backwards-compatible level supported
by this instance.

Release 0.1.6 is the first release that reports the Nvim version and API
level.

    metadata['version'] = {
      major: 0,
      minor: 1,
      patch: 6,
      api_level: 1,
      api_compatible: 0,
      api_prerelease: false,
    }

The API level may remain unchanged across Nvim releases if the API has
not changed.

When changing the API,
    - set NVIM_API_PRERELEASE to true
    - increment NVIM_API_LEVEL (at most once per Nvim version)
    - adjust NVIM_API_LEVEL_COMPAT if backwards-compatibility was broken

api_level_0.mpack was generated from Nvim 0.1.5 with:
    nvim --api-info

1 files changed, 0 insertions, 65 deletions

diff --git a/test/functional/api/compatibility_spec.lua b/test/functional/api/compatibility_spec.lua
deleted file mode 100644
index e0fc625b46..0000000000
--- a/test/functional/api/compatibility_spec.lua
+++ /dev/null
@@ -1,65 +0,0 @@
-
-local helpers = require('test.functional.helpers')(after_each)
-local lfs = require('lfs')
-local mpack = require('mpack')
-local clear, eq, neq = helpers.clear, helpers.eq, helpers.neq
-
-local read_mpack_file = function(fname)
-  local fd = io.open(fname, 'rb')
-  local data = fd:read('*a')
-  fd:close()
-  local unpack = mpack.Unpacker()
-  return unpack(data)
-end
-
--- ignore metadata in API function spec
-local remove_function_metadata = function(fspec)
-  fspec['can_fail'] = nil
-  fspec['async'] = nil
-  fspec['method'] = nil
-  fspec['since'] = nil
-  fspec['deprecated_since'] = nil
-  fspec['receives_channel_id'] = nil
-  for idx,_  in ipairs(fspec['parameters']) do
-    fspec['parameters'][idx][2] = ''
-  end
-end
-
-clear()
-local api_level = helpers.call('api_info')['api_level']
-
-describe('api compatibility', function()
-  before_each(clear)
-
-  it("version metadata is sane", function()
-    local info = helpers.call('api_info')
-    local current = info['api_level']['current']
-    local compatibility = info['api_level']['compatibility']
-    neq(current, nil)
-    neq(compatibility, nil)
-    assert(current >= compatibility)
-  end)
-
-  for ver = api_level['compatibility'], api_level['current'] do
-    local path = 'test/functional/fixtures/api-info/' .. tostring(ver) .. '.mpack'
-    it('are backwards compatible with api level '..ver, function()
-      if lfs.attributes(path,"mode") ~= "file" then
-        pending("No fixture found, skipping test")
-        return
-      end
-
-      local old_api = read_mpack_file(path)
-      local api = helpers.call('api_info')
-
-      for _, fspec in ipairs(old_api['functions']) do
-        remove_function_metadata(fspec)
-        for _, fspec_new in ipairs(api['functions']) do
-          if fspec['name'] == fspec_new['name'] then
-            remove_function_metadata(fspec_new)
-            eq(fspec, fspec_new)
-          end
-        end
-      end
-    end)
-  end
-end)