Warn about missing libraries in brew info

Library/Homebrew/cmd/info.rb

@@ -642,6 +642,9 @@ def info_formula(formula, shadowed_by: nil)
         kegs = shadowing_formula ? [] : formula.installed_kegs
         installed = kegs.any?
         outdated = installed && formula.outdated?
+        missing_libraries, missing_library_deps = formula.missing_library_linkage if installed
+        missing_libraries ||= []
+        missing_library_deps ||= Set.new
         if outdated && (upgrade_version = specs.first.presence)
           installed_version = formula.linked_version ||
                               kegs.max_by(&:scheme_and_version)&.version
@@ -656,6 +659,7 @@ def info_formula(formula, shadowed_by: nil)
         end
         name_with_status = pretty_install_status(
           title_name,
+          warning:    missing_libraries.present?,
           installed:,
           outdated:,
           deprecated: formula.deprecated?,
@@ -753,11 +757,17 @@ def info_formula(formula, shadowed_by: nil)
 
           tab_deps = (kegs.any? && type != "build") ? tab_runtime_deps : nil
           "#{type.capitalize} (#{deps.count}): " \
-            "#{decorate_dependencies(deps, tab_runtime_deps: tab_deps, mark_uninstalled: kegs.any?)}"
+            "#{decorate_dependencies(deps, tab_runtime_deps: tab_deps, mark_uninstalled: kegs.any?,
+                                     missing_library_deps:)}"
         end
         if dependency_lines.present? || tab_runtime_deps.present? || installed_dependents.any?
           ohai "Dependencies"
           puts dependency_lines
+          missing_library_names = missing_libraries.map { |lib| File.basename(lib) }.uniq
+          if missing_library_names.present?
+            decorated = missing_library_names.map { |lib| pretty_uninstalled(lib, bold: false) }.join(", ")
+            puts "Missing libraries (#{missing_library_names.count}): #{decorated}"
+          end
           if tab_runtime_deps.present?
             installed_count = tab_runtime_deps.count do |dep|
               dep_name = dep["full_name"]&.then { Utils.name_from_full_name(it) }
@@ -869,11 +879,13 @@ def installed_section_lines(formula, verbose: false)
       end
 
       sig {
-        params(dependencies:     T::Array[Dependency],
-               tab_runtime_deps: T.nilable(T::Array[T::Hash[String, T.untyped]]),
-               mark_uninstalled: T::Boolean).returns(String)
+        params(dependencies:         T::Array[Dependency],
+               tab_runtime_deps:     T.nilable(T::Array[T::Hash[String, T.untyped]]),
+               mark_uninstalled:     T::Boolean,
+               missing_library_deps: T::Set[String]).returns(String)
       }
-      def decorate_dependencies(dependencies, tab_runtime_deps: nil, mark_uninstalled: true)
+      def decorate_dependencies(dependencies, tab_runtime_deps: nil, mark_uninstalled: true,
+                                missing_library_deps: Set.new)
         dependencies.map do |dep|
           display = dep_display_s(dep)
           full_name = tab_runtime_deps&.find do |d|
@@ -889,7 +901,8 @@ def decorate_dependencies(dependencies, tab_runtime_deps: nil, mark_uninstalled:
           end
           installed ||= formula.any_version_installed? if !installed && formula
           outdated = T.let(installed && formula&.outdated? == true, T::Boolean)
-          pretty_install_status(display, installed:, outdated:, mark_uninstalled:)
+          warning = missing_library_deps.include?(Utils.name_from_full_name(dep.name))
+          pretty_install_status(display, warning:, installed:, outdated:, mark_uninstalled:)
         end.join(", ")
       end
 

Library/Homebrew/formula.rb

@@ -3441,6 +3441,20 @@ def undeclared_runtime_dependencies
 
   public
 
+  sig { returns([T::Array[String], T::Set[String]]) }
+  def missing_library_linkage
+    keg = any_installed_keg
+    return [[], Set.new] unless keg&.directory?
+
+    CacheStoreDatabase.use(:linkage) do |db|
+      typed_db = T.cast(db, CacheStoreDatabase[String, T::Hash[T.any(String, Symbol), T.anything]])
+      linkage_checker = LinkageChecker.new(keg, self, cache_db: typed_db)
+      own_libraries = (linkage_checker.broken_deps.fetch(name, []) + linkage_checker.broken_dylibs.to_a).uniq.sort
+      dependency_names = linkage_checker.broken_deps.keys.reject { |dep| dep == name }.to_set
+      [own_libraries, dependency_names]
+    end
+  end
+
   # To call out to the system, we use the `system` method and we prefer
   # you give the args separately as in the line below, otherwise a subshell
   # has to be opened first.

Library/Homebrew/linkage_checker.rb

@@ -23,7 +23,10 @@ class LinkageChecker
   attr_reader :indirect_deps, :undeclared_deps, :unwanted_system_dylibs
 
   sig { returns(T::Set[String]) }
-  attr_reader :system_dylibs
+  attr_reader :system_dylibs, :broken_dylibs
+
+  sig { returns(T::Hash[String, T::Array[String]]) }
+  attr_reader :broken_deps
 
   sig {
     params(

Library/Homebrew/test/cmd/info_spec.rb

@@ -284,7 +284,7 @@ def installed_info_cask
       option "with-foo", "Build with foo"
     end
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Installs from source: yes/).to_stdout
@@ -332,7 +332,7 @@ def installed_info_cask
       deprecate! date: "2024-01-01", because: :versioned_formula
     end
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/==> .*testball.*\(deprecated\):/).to_stdout
@@ -350,7 +350,7 @@ def installed_info_cask
       disable! date: "2024-01-01", because: :unmaintained
     end
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/==> .*testball.*\(disabled\):/).to_stdout
@@ -475,7 +475,7 @@ def installed_info_cask
       url "https://brew.sh/testball-0.1.tar.gz"
     end
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula, shadowed_by: Tap.fetch("homebrew/core")) }
       .to output(%r{Warning: `testball` shadows `homebrew/core/testball`}).to_stdout
@@ -595,7 +595,7 @@ def installed_info_cask
     dependent_tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
     allow(direct_dependency).to receive(:satisfied?).and_return(true)
 
     expected_output = Regexp.new(
@@ -637,7 +637,7 @@ def installed_info_cask
     end
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/^Dependents \(2\): another-dependent, some-dependent$/).to_stdout
@@ -673,7 +673,7 @@ def installed_info_cask
     installed_dep_tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
     allow(direct_dependency).to receive(:satisfied?).and_return(true)
 
     expect { info.send(:info_formula, formula) }
@@ -702,7 +702,7 @@ def installed_info_cask
     tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*bar.*✘/).to_stdout
@@ -739,7 +739,7 @@ def installed_info_cask
     allow(direct_dependency).to receive(:to_formula).and_return(bar_formula)
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*bar.*✔/).to_stdout
@@ -776,7 +776,7 @@ def installed_info_cask
     allow(direct_dependency).to receive(:to_formula).and_return(bar_formula)
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*bar.*↑/).to_stdout
@@ -806,7 +806,7 @@ def installed_info_cask
     allow(direct_dependency).to receive(:to_formula).and_return(bar_formula)
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*bar.*✔/).to_stdout
@@ -836,7 +836,7 @@ def installed_info_cask
     allow(direct_dependency).to receive(:to_formula).and_return(bar_formula)
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*bar.*↑/).to_stdout
@@ -866,7 +866,7 @@ def installed_info_cask
     allow(direct_dependency).to receive(:to_formula).and_return(pkgconf_formula)
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*pkg-config.*✔/).to_stdout
@@ -886,7 +886,7 @@ def installed_info_cask
     end
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): bar\n/).to_stdout
@@ -913,7 +913,7 @@ def installed_info_cask
     tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*bar.*✘/).to_stdout
@@ -946,7 +946,7 @@ def installed_info_cask
     bar_tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(/Required \(1\): .*bar.*↑/).to_stdout
@@ -1071,7 +1071,7 @@ def installed_info_cask
     tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to output(a_string_including("==> Binaries\nanother\ndaemon\ntestball\n")).to_stdout
@@ -1121,7 +1121,7 @@ def installed_info_cask
     tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to not_to_output(/==> Binaries/).to_stdout
@@ -1144,7 +1144,7 @@ def installed_info_cask
     tab.write
 
     allow(info).to receive(:github_info).with(formula).and_return("https://example.com/testball.rb")
-    allow(formula).to receive(:core_formula?).and_return(false)
+    allow(formula).to receive_messages(core_formula?: false, missing_library_linkage: [[], Set.new])
 
     expect { info.send(:info_formula, formula) }
       .to not_to_output(/==> Binaries/).to_stdout

Library/Homebrew/test/formula_spec.rb

@@ -1625,6 +1625,44 @@ def post_install; end
     end
   end
 
+  describe "#missing_library_linkage" do
+    let(:f) do
+      formula("foo") do
+        T.bind(self, T.class_of(Formula))
+        url "foo-1.0"
+      end
+    end
+
+    it "returns empty when no keg is installed" do
+      allow(f).to receive(:any_installed_keg).and_return(nil)
+      expect(f.missing_library_linkage).to eq([[], Set.new])
+    end
+
+    it "returns only the formula's own and orphan libraries, excluding dependency-owned ones" do
+      keg = instance_double(Keg, directory?: true)
+      allow(f).to receive(:any_installed_keg).and_return(keg)
+      linkage_checker = instance_double(
+        LinkageChecker,
+        broken_deps:   { "foo" => ["libfoo.1.dylib"], "gmp" => ["libgmp.10.dylib"] },
+        broken_dylibs: Set["liborphan.2.dylib"],
+      )
+      allow(LinkageChecker).to receive(:new).and_return(linkage_checker)
+      expect(f.missing_library_linkage.first).to eq(["libfoo.1.dylib", "liborphan.2.dylib"])
+    end
+
+    it "returns the dependency names that own missing libraries, excluding the formula itself" do
+      keg = instance_double(Keg, directory?: true)
+      allow(f).to receive(:any_installed_keg).and_return(keg)
+      linkage_checker = instance_double(
+        LinkageChecker,
+        broken_deps:   { "foo" => ["libfoo.1.dylib"], "gmp" => ["libgmp.10.dylib"] },
+        broken_dylibs: Set.new,
+      )
+      allow(LinkageChecker).to receive(:new).and_return(linkage_checker)
+      expect(f.missing_library_linkage.last).to eq(Set["gmp"])
+    end
+  end
+
   specify "requirements" do
     # don't try to load/fetch gcc/glibc
     allow(DevelopmentTools).to receive_messages(needs_libc_formula?: false, needs_compiler_formula?: false)

Library/Homebrew/utils/output.rb

@@ -264,7 +264,7 @@ def pretty_installed(string)
 
       sig { params(string: String, bold: T::Boolean).returns(String) }
       def pretty_upgradable(string, bold: true)
-        weight = bold ? Tty.bold : ""
+        weight = bold ? Tty.bold.to_s : ""
         if !$stdout.tty?
           string
         elsif Homebrew::EnvConfig.no_emoji?
@@ -294,29 +294,45 @@ def pretty_disabled(string)
 
       # Keep status labels, colours and emoji in sync with
       # `pretty_uninstalled` in Library/Homebrew/utils.sh.
-      sig { params(string: String).returns(String) }
-      def pretty_uninstalled(string)
+      sig { params(string: String, bold: T::Boolean).returns(String) }
+      def pretty_uninstalled(string, bold: true)
+        weight = bold ? Tty.bold.to_s : ""
+        if !$stdout.tty?
+          string
+        elsif Homebrew::EnvConfig.no_emoji?
+          Formatter.error("#{weight}#{string} (uninstalled)#{Tty.reset}")
+        else
+          "#{weight}#{string} #{Formatter.error("✘")}#{Tty.reset}"
+        end
+      end
+
+      sig { params(string: String, bold: T::Boolean).returns(String) }
+      def pretty_warning(string, bold: true)
+        weight = bold ? Tty.bold.to_s : ""
         if !$stdout.tty?
           string
         elsif Homebrew::EnvConfig.no_emoji?
-          Formatter.error("#{Tty.bold}#{string} (uninstalled)#{Tty.reset}")
+          Formatter.warning("#{weight}#{string} (warning)#{Tty.reset}")
         else
-          "#{Tty.bold}#{string} #{Formatter.error("✘")}#{Tty.reset}"
+          "#{weight}#{string} #{Formatter.warning("⚠")}#{Tty.reset}"
         end
       end
 
       sig {
-        params(string: String, installed: T::Boolean, outdated: T::Boolean, deprecated: T::Boolean,
-               disabled: T::Boolean, mark_uninstalled: T::Boolean, bold: T::Boolean).returns(String)
+        params(string: String, installed: T::Boolean, warning: T::Boolean, outdated: T::Boolean,
+               deprecated: T::Boolean, disabled: T::Boolean, mark_uninstalled: T::Boolean,
+               bold: T::Boolean).returns(String)
       }
-      def pretty_install_status(string, installed:, outdated: false, deprecated: false, disabled: false,
-                                mark_uninstalled: true, bold: true)
-        status = if installed && outdated
+      def pretty_install_status(string, installed:, warning: false, outdated: false, deprecated: false,
+                                disabled: false, mark_uninstalled: true, bold: true)
+        status = if warning
+          pretty_warning(string, bold:)
+        elsif installed && outdated
           pretty_upgradable(string, bold:)
         elsif installed
           pretty_installed(string)
         elsif mark_uninstalled
-          pretty_uninstalled(string)
+          pretty_uninstalled(string, bold:)
         else
           string
         end