fix(npm): set install-strategy on npm >= 9

Closes #1175.

lua/mason-core/installer/managers/npm.lua

@@ -4,9 +4,25 @@ local installer = require "mason-core.installer"
 local log = require "mason-core.log"
 local path = require "mason-core.path"
 local platform = require "mason-core.platform"
+local semver = require "mason-core.semver"
+local spawn = require "mason-core.spawn"
 
 local M = {}
 
+---@async
+---@param predicate fun(npm_version: Semver): boolean
+---@return boolean
+local function npm_version_satisfies(predicate)
+    return Result.try(function(try)
+        local npm_versions = try(spawn.npm { "version", "--json" }).stdout
+        ---@type { npm: string }
+        local versions = try(Result.pcall(vim.json.decode, npm_versions))
+        ---@type Semver
+        local npm_version = try(semver.parse(versions.npm))
+        return predicate(npm_version)
+    end):get_or_else(false)
+end
+
 ---@async
 function M.init()
     log.debug "npm: init"
@@ -18,7 +34,7 @@ function M.init()
             "--scope=mason",
         })
 
-        -- Use global-style. The reasons for this are:
+        -- Use shallow install-strategy. The reasons for this are:
         --   a) To avoid polluting the executables (aka bin-links) that npm creates.
         --   b) The installation is, after all, more similar to a "global" installation. We don't really gain
         --      any of the benefits of not using global style (e.g., deduping the dependency tree).
@@ -27,7 +43,11 @@ function M.init()
         --  is a bit unreliable across npm versions (especially <7), so we take extra measures to avoid
         --  inadvertently polluting global npm config.
         try(Result.pcall(function()
-            ctx.fs:append_file(".npmrc", "global-style=true")
+            if npm_version_satisfies(_.gte(semver.new "9.0.0")) then
+                ctx.fs:append_file(".npmrc", "\ninstall-strategy=shallow")
+            else
+                ctx.fs:append_file(".npmrc", "\nglobal-style=true")
+            end
         end))
 
         ctx.stdio_sink.stdout "Initialized npm root\n"

lua/mason-core/semver.lua

@@ -4,9 +4,14 @@ local semver = require "mason-vendor.semver"
 local M = {}
 
 ---@param version string
-function M.parse(version)
+function M.new(version)
     version = version:gsub("^v", "")
-    return Result.pcall(semver, version)
+    return semver(version)
+end
+
+---@param version string
+function M.parse(version)
+    return Result.pcall(M.new, version)
 end
 
 return M

lua/mason-vendor/semver.lua

@@ -144,18 +144,28 @@ local function smallerPrerelease(mine, other)
   return smallerIdList(splitByDot(mine), splitByDot(other))
 end
 
+---@class ISemver
 local methods = {}
 
+---@return Semver
 function methods:nextMajor()
   return semver(self.major + 1, 0, 0)
 end
+---@return Semver
 function methods:nextMinor()
   return semver(self.major, self.minor + 1, 0)
 end
+---@return Semver
 function methods:nextPatch()
   return semver(self.major, self.minor, self.patch + 1)
 end
 
+---@class Semver : ISemver
+---@field major integer
+---@field minor integer
+---@field patch integer
+---@field prerelease? string
+---@field build? string
 local mt = { __index = methods }
 function mt:__eq(other)
   return self.major == other.major and
@@ -188,6 +198,7 @@ function mt:__tostring()
   return table.concat(buffer)
 end
 
+---@return Semver
 local function new(major, minor, patch, prerelease, build)
   assert(major, "At least one parameter is needed")
 

tests/mason-core/installer/managers/npm_spec.lua

@@ -1,12 +1,19 @@
+local Result = require "mason-core.result"
 local installer = require "mason-core.installer"
 local match = require "luassert.match"
 local npm = require "mason-core.installer.managers.npm"
+local spawn = require "mason-core.spawn"
 local stub = require "luassert.stub"
 
 describe("npm manager", function()
     it("should init package.json", function()
         local ctx = create_dummy_context()
         stub(ctx.fs, "append_file")
+        stub(spawn, "npm")
+        spawn.npm.returns(Result.success {})
+        spawn.npm.on_call_with({ "version", "--json" }).returns(Result.success {
+            stdout = [[ { "npm": "8.1.0" } ]],
+        })
         installer.exec_in_context(ctx, function()
             npm.init()
         end)
@@ -18,7 +25,28 @@ describe("npm manager", function()
             "--scope=mason",
         }
         assert.spy(ctx.fs.append_file).was_called(1)
-        assert.spy(ctx.fs.append_file).was_called_with(match.is_ref(ctx.fs), ".npmrc", "global-style=true")
+        assert.spy(ctx.fs.append_file).was_called_with(match.is_ref(ctx.fs), ".npmrc", "\nglobal-style=true")
+    end)
+
+    it("should use install-strategy on npm >= 9", function()
+        local ctx = create_dummy_context()
+        stub(ctx.fs, "append_file")
+        stub(spawn, "npm")
+        spawn.npm.returns(Result.success {})
+        spawn.npm.on_call_with({ "version", "--json" }).returns(Result.success {
+            stdout = [[ { "npm": "9.1.0" } ]],
+        })
+        installer.exec_in_context(ctx, function()
+            npm.init()
+        end)
+
+        assert.spy(ctx.spawn.npm).was_called(1)
+        assert.spy(ctx.spawn.npm).was_called_with {
+            "init",
+            "--yes",
+            "--scope=mason",
+        }
+        assert.spy(ctx.fs.append_file).was_called_with(match.is_ref(ctx.fs), ".npmrc", "\ninstall-strategy=shallow")
     end)
 
     it("should install", function()