cmd/*env-sync: add HOMEBREW_ENV_SYNC_STRICT mode.

If this variable is set, `brew *env-sync` will only sync the exact
installed versions of formulae rather than all the patch (or, for node,
minor and patch) versions.

Library/Homebrew/cmd/nodenv-sync.rb

@@ -55,14 +55,24 @@ module Homebrew
         minor_version = version.minor.to_i || 0
         patch_version = version.patch.to_i || 0
 
-        (0..minor_version).each do |minor|
-          (0..patch_version).each do |patch|
+        minor_version_range, patch_version_range = if Homebrew::EnvConfig.env_sync_strict?
+          # Only create symlinks for the exact installed patch version.
+          # e.g. 23.9.0 => 23.9.0
+          [[minor_version], [patch_version]]
+        else
+          # Create folder symlinks for all patch versions to the latest patch version
+          # e.g. 23.9.0 => 23.10.1
+          [0..minor_version, 0..patch_version]
+        end
+
+        minor_version_range.each do |minor|
+          patch_version_range.each do |patch|
             link_path = nodenv_versions/"#{major_version}.#{minor}.#{patch}"
             # Don't clobber existing user installations.
             next if link_path.exist? && !link_path.symlink?
 
             FileUtils.rm_f link_path
-            FileUtils.ln_sf path, link_path
+            FileUtils.ln_s path, link_path
           end
         end
       end

Library/Homebrew/cmd/pyenv-sync.rb

@@ -54,22 +54,29 @@ module Homebrew
         minor_version = version.minor.to_i
         patch_version = version.patch.to_i
 
-        (0..patch_version).each do |patch|
+        patch_version_range = if Homebrew::EnvConfig.env_sync_strict?
+          # Only create symlinks for the exact installed patch version.
+          # e.g. 3.11.0 => 3.11.0
+          [patch_version]
+        else
           # Create folder symlinks for all patch versions to the latest patch version
-          # (eg. 3.11.0 -> 3.11.3).
+          # e.g. 3.11.0 => 3.11.3
+          0..patch_version
+        end
+
+        patch_version_range.each do |patch|
           link_path = pyenv_versions/"#{major_version}.#{minor_version}.#{patch}"
 
           # Don't clobber existing user installations.
           next if link_path.exist? && !link_path.symlink?
 
           FileUtils.rm_f link_path
-          FileUtils.ln_sf path, link_path
+          FileUtils.ln_s path, link_path
 
           # Create an unversioned symlinks
           # This is what pyenv expects to find in ~/.pyenv/versions/___/bin'.
           # Without this, `python3`, `pip3` do not exist and pyenv falls back to system Python.
           # (eg. python3 -> python3.11, pip3 -> pip3.11)
-
           executables = %w[python3 pip3 wheel3 idle3 pydoc3]
           executables.each do |executable|
             major_link_path = link_path/"bin/#{executable}"
@@ -77,8 +84,14 @@ module Homebrew
             # Don't clobber existing user installations.
             next if major_link_path.exist? && !major_link_path.symlink?
 
+            executable_link_path = link_path/"bin/#{executable}.#{minor_version}"
             FileUtils.rm_f major_link_path
-            FileUtils.ln_s link_path/"bin/#{executable}.#{minor_version}", major_link_path
+
+            begin
+              FileUtils.ln_s executable_link_path, major_link_path
+            rescue => e
+              opoo "Failed to link #{executable_link_path} to #{major_link_path}: #{e}"
+            end
           end
         end
       end

Library/Homebrew/cmd/rbenv-sync.rb

@@ -55,13 +55,23 @@ module Homebrew
         minor_version = version.minor.to_i
         patch_version = version.patch.to_i || 0
 
-        (0..patch_version).each do |patch|
+        patch_version_range = if Homebrew::EnvConfig.env_sync_strict?
+          # Only create symlinks for the exact installed patch version.
+          # e.g. 3.4.0 => 3.4.0
+          [patch_version]
+        else
+          # Create folder symlinks for all patch versions to the latest patch version
+          # e.g. 3.4.0 => 3.4.2
+          0..patch_version
+        end
+
+        patch_version_range.each do |patch|
           link_path = rbenv_versions/"#{major_version}.#{minor_version}.#{patch}"
           # Don't clobber existing user installations.
           next if link_path.exist? && !link_path.symlink?
 
           FileUtils.rm_f link_path
-          FileUtils.ln_sf path, link_path
+          FileUtils.ln_s path, link_path
         end
       end
     end

Library/Homebrew/env_config.rb

@@ -195,6 +195,10 @@ module Homebrew
                       "editors will do strange things in this case.",
         default_text: "`$EDITOR` or `$VISUAL`.",
       },
+      HOMEBREW_ENV_SYNC_STRICT:                  {
+        description: "If set, `brew *env-sync` will only sync the exact installed versions of formulae.",
+        boolean:     true,
+      },
       HOMEBREW_EVAL_ALL:                         {
         description: "If set, `brew` commands evaluate all formulae and casks, executing their arbitrary code, by " \
                      "default without requiring `--eval-all`. Required to cache formula and cask descriptions.",

Library/Homebrew/sorbet/rbi/dsl/homebrew/env_config.rbi

@@ -115,6 +115,9 @@ module Homebrew::EnvConfig
     sig { returns(T.nilable(::String)) }
     def editor; end
 
+    sig { returns(T::Boolean) }
+    def env_sync_strict?; end
+
     sig { returns(T::Boolean) }
     def eval_all?; end