refactor!: refactor installer internals and add new Package class methods (#1523)

This contains the following changes:
1) `Package:install()` now accepts a second, optional, callback argument which is called when installation finishes
   (successfully or not).
2) Adds a `Package:is_installing()` method.

This contains the following breaking changes:
1) `Package:install()` will now error when called while an installation is already ongoing. Use the new
   `Package:is_installing()` method to check whether an installation is already running.

This also refactors large portions of the tests by removing test globals, removing async_test, and adding the
`mason-test` Lua module instead. Test helpers via globals are problematic to work with due to not being detected through
tools like the Lua language server without additional configuration. This has been replaced with a Lua module
`mason-test`. `async_test` has also been removed in favour of explicitly making use of the `mason-core.async` API. These
changes stands for a significant portion of the diff.

1 files changed, 108 insertions, 0 deletions

diff --git a/lua/mason-core/installer/context/fs.lua b/lua/mason-core/installer/context/fs.lua
new file mode 100644
index 00000000..5c51fb56
--- /dev/null
+++ b/lua/mason-core/installer/context/fs.lua
@@ -0,0 +1,108 @@
+local fs = require "mason-core.fs"
+local log = require "mason-core.log"
+local path = require "mason-core.path"
+
+---@class InstallContextFs
+---@field private cwd InstallContextCwd
+local InstallContextFs = {}
+InstallContextFs.__index = InstallContextFs
+
+---@param cwd InstallContextCwd
+function InstallContextFs.new(cwd)
+    return setmetatable({ cwd = cwd }, InstallContextFs)
+end
+
+---@async
+---@param rel_path string The relative path from the current working directory to the file to append.
+---@param contents string
+function InstallContextFs:append_file(rel_path, contents)
+    return fs.async.append_file(path.concat { self.cwd:get(), rel_path }, contents)
+end
+
+---@async
+---@param rel_path string The relative path from the current working directory to the file to write.
+---@param contents string
+function InstallContextFs:write_file(rel_path, contents)
+    return fs.async.write_file(path.concat { self.cwd:get(), rel_path }, contents)
+end
+
+---@async
+---@param rel_path string The relative path from the current working directory to the file to read.
+function InstallContextFs:read_file(rel_path)
+    return fs.async.read_file(path.concat { self.cwd:get(), rel_path })
+end
+
+---@async
+---@param rel_path string The relative path from the current working directory.
+function InstallContextFs:file_exists(rel_path)
+    return fs.async.file_exists(path.concat { self.cwd:get(), rel_path })
+end
+
+---@async
+---@param rel_path string The relative path from the current working directory.
+function InstallContextFs:dir_exists(rel_path)
+    return fs.async.dir_exists(path.concat { self.cwd:get(), rel_path })
+end
+
+---@async
+---@param rel_path string The relative path from the current working directory.
+function InstallContextFs:rmrf(rel_path)
+    return fs.async.rmrf(path.concat { self.cwd:get(), rel_path })
+end
+
+---@async
+---@param rel_path string The relative path from the current working directory.
+function InstallContextFs:unlink(rel_path)
+    return fs.async.unlink(path.concat { self.cwd:get(), rel_path })
+end
+
+---@async
+---@param old_path string
+---@param new_path string
+function InstallContextFs:rename(old_path, new_path)
+    return fs.async.rename(path.concat { self.cwd:get(), old_path }, path.concat { self.cwd:get(), new_path })
+end
+
+---@async
+---@param dir_path string
+function InstallContextFs:mkdir(dir_path)
+    return fs.async.mkdir(path.concat { self.cwd:get(), dir_path })
+end
+
+---@async
+---@param dir_path string
+function InstallContextFs:mkdirp(dir_path)
+    return fs.async.mkdirp(path.concat { self.cwd:get(), dir_path })
+end
+
+---@async
+---@param file_path string
+function InstallContextFs:chmod_exec(file_path)
+    local bit = require "bit"
+    -- see chmod(2)
+    local USR_EXEC = 0x40
+    local GRP_EXEC = 0x8
+    local ALL_EXEC = 0x1
+    local EXEC = bit.bor(USR_EXEC, GRP_EXEC, ALL_EXEC)
+    local fstat = self:fstat(file_path)
+    if bit.band(fstat.mode, EXEC) ~= EXEC then
+        local plus_exec = bit.bor(fstat.mode, EXEC)
+        log.fmt_debug("Setting exec flags on file %s %o -> %o", file_path, fstat.mode, plus_exec)
+        self:chmod(file_path, plus_exec) -- chmod +x
+    end
+end
+
+---@async
+---@param file_path string
+---@param mode integer
+function InstallContextFs:chmod(file_path, mode)
+    return fs.async.chmod(path.concat { self.cwd:get(), file_path }, mode)
+end
+
+---@async
+---@param file_path string
+function InstallContextFs:fstat(file_path)
+    return fs.async.fstat(path.concat { self.cwd:get(), file_path })
+end
+
+return InstallContextFs