Lint: Remove useless assignments (#12648)

samples/binary-trees.cr

@@ -31,7 +31,6 @@ stretch_depth = max_depth + 1
 stretch_tree = bottom_up_tree(0, stretch_depth)
 
 puts "stretch tree of depth #{stretch_depth}\t check: #{item_check(stretch_tree)}"
-stretch_tree = nil
 
 long_lived_tree = bottom_up_tree(0, max_depth)
 

samples/mt_gc_test.cr

@@ -110,7 +110,7 @@ class Context
     @threads_state.set(State::Wait)
 
     # spin wait for threads to finish the round
-    while (c = @threads_reached.get) < @threads
+    while @threads_reached.get < @threads
     end
     log "All threads_reached!"
   end

samples/red_black_tree.cr

@@ -328,10 +328,10 @@ class RedBlackTreeRunner
     @n = n
 
     random = Random.new(1234) # repeatable random seq
-    @a1 = Array(Int32).new(n) { rand(99_999) }
+    @a1 = Array(Int32).new(n) { random.rand(99_999) }
 
     random = Random.new(4321) # repeatable random seq
-    @a2 = Array(Int32).new(n) { rand(99_999) }
+    @a2 = Array(Int32).new(n) { random.rand(99_999) }
 
     @tree = RedBlackTree.new
   end

samples/wordcount.cr

@@ -50,4 +50,4 @@ end
 
 in_filenames = ARGV
 
-do_work ARGV, output_filename, ignore_case
+do_work in_filenames, output_filename, ignore_case

spec/compiler/macro/macro_methods_spec.cr

@@ -3100,27 +3100,27 @@ module Crystal
       it "returns true if file exists" do
         run(%q<
           {{file_exists?("#{__DIR__}/../data/build")}} ? 10 : 20
-          >, filename = __FILE__).to_i.should eq(10)
+          >, filename: __FILE__).to_i.should eq(10)
       end
 
       it "returns false if file doesn't exist" do
         run(%q<
           {{file_exists?("#{__DIR__}/../data/build_foo")}} ? 10 : 20
-          >, filename = __FILE__).to_i.should eq(20)
+          >, filename: __FILE__).to_i.should eq(20)
       end
     end
 
     context "with relative path" do
       it "reads file (exists)" do
         run(%q<
           {{file_exists?("spec/compiler/data/build")}} ? 10 : 20
-          >, filename = __FILE__).to_i.should eq(10)
+          >, filename: __FILE__).to_i.should eq(10)
       end
 
       it "reads file (doesn't exist)" do
         run(%q<
           {{file_exists?("spec/compiler/data/build_foo")}} ? 10 : 20
-          >, filename = __FILE__).to_i.should eq(20)
+          >, filename: __FILE__).to_i.should eq(20)
       end
     end
   end
@@ -3130,7 +3130,7 @@ module Crystal
       it "reads file (exists)" do
         run(%q<
           {{read_file("#{__DIR__}/../data/build")}}
-          >, filename = __FILE__).to_string.should eq(File.read("#{__DIR__}/../data/build"))
+          >, filename: __FILE__).to_string.should eq(File.read("#{__DIR__}/../data/build"))
       end
 
       it "reads file (doesn't exist)" do
@@ -3145,7 +3145,7 @@ module Crystal
       it "reads file (exists)" do
         run(%q<
           {{read_file("spec/compiler/data/build")}}
-          >, filename = __FILE__).to_string.should eq(File.read("spec/compiler/data/build"))
+          >, filename: __FILE__).to_string.should eq(File.read("spec/compiler/data/build"))
       end
 
       it "reads file (doesn't exist)" do
@@ -3162,15 +3162,15 @@ module Crystal
       it "reads file (doesn't exist)" do
         run(%q<
           {{read_file?("#{__DIR__}/../data/build_foo")}} ? 10 : 20
-          >, filename = __FILE__).to_i.should eq(20)
+          >, filename: __FILE__).to_i.should eq(20)
       end
     end
 
     context "with relative path" do
       it "reads file (doesn't exist)" do
         run(%q<
           {{read_file?("spec/compiler/data/build_foo")}} ? 10 : 20
-          >, filename = __FILE__).to_i.should eq(20)
+          >, filename: __FILE__).to_i.should eq(20)
       end
     end
   end

spec/compiler/parser/warnings_spec.cr

@@ -3,7 +3,7 @@ require "../../support/syntax"
 private def assert_parser_warning(source, message, *, file = __FILE__, line = __LINE__)
   parser = Parser.new(source)
   parser.filename = "/foo/bar/baz.cr"
-  node = parser.parse
+  parser.parse
 
   warnings = parser.warnings.infos
   warnings.size.should eq(1), file: file, line: line

spec/compiler/semantic/class_spec.cr

@@ -35,7 +35,7 @@ describe "Semantic: class" do
   end
 
   it "types generic of generic type" do
-    result = assert_type("
+    assert_type("
       class Foo(T)
         def set
           @coco = 2

spec/compiler/semantic/instance_var_spec.cr

@@ -4367,7 +4367,7 @@ describe "Semantic: instance var" do
   end
 
   it "declares instance var of generic class" do
-    result = assert_type("
+    assert_type("
       class Foo(T)
         @x : T
 
@@ -4385,7 +4385,7 @@ describe "Semantic: instance var" do
   end
 
   it "declares instance var of generic class after reopen" do
-    result = assert_type("
+    assert_type("
       class Foo(T)
       end
 

spec/compiler/semantic/virtual_spec.cr

@@ -607,7 +607,7 @@ describe "Semantic: virtual" do
   end
 
   it "uses virtual type as generic type if class is abstract" do
-    result = assert_type("
+    assert_type("
       abstract class Foo
       end
 
@@ -619,7 +619,7 @@ describe "Semantic: virtual" do
   end
 
   it "uses virtual type as generic type if class is abstract even in union" do
-    result = assert_type("
+    assert_type("
       abstract class Foo
       end
 

spec/compiler/semantic/warnings_spec.cr

@@ -230,7 +230,7 @@ describe "Semantic: warnings" do
           compiler.warnings.level = :all
           compiler.warnings.exclude_lib_path = true
           compiler.prelude = "empty"
-          result = compiler.compile Compiler::Source.new(main_filename, File.read(main_filename)), output_filename
+          compiler.compile Compiler::Source.new(main_filename, File.read(main_filename)), output_filename
 
           compiler.warnings.infos.size.should eq(1)
         end
@@ -399,7 +399,7 @@ describe "Semantic: warnings" do
           compiler.warnings.level = :all
           compiler.warnings.exclude_lib_path = true
           compiler.prelude = "empty"
-          result = compiler.compile Compiler::Source.new(main_filename, File.read(main_filename)), output_filename
+          compiler.compile Compiler::Source.new(main_filename, File.read(main_filename)), output_filename
 
           compiler.warnings.infos.size.should eq(1)
         end

spec/spec_helper.cr

@@ -80,7 +80,6 @@ end
 def assert_normalize(from, to, flags = nil, *, file = __FILE__, line = __LINE__)
   program = new_program
   program.flags.concat(flags.split) if flags
-  normalizer = Normalizer.new(program)
   from_nodes = Parser.parse(from)
   to_nodes = program.normalize(from_nodes)
   to_nodes.to_s.strip.should eq(to.strip), file: file, line: line

spec/std/deque_spec.cr

@@ -637,7 +637,7 @@ describe "Deque" do
       a = Deque{1, 2, 3}
       count = 0
       it = a.each_index
-      a.each_index.each do
+      it.each do
         count += 1
         a.clear
       end

spec/std/hash_spec.cr

@@ -1257,7 +1257,7 @@ describe "Hash" do
     it { {"a" => 2, "b" => 3}.reject(["b", "a"]).should eq({} of String => Int32) }
     it "does not change current hash" do
       h = {"a" => 3, "b" => 6, "c" => 9}
-      h2 = h.reject("b", "c")
+      h.reject("b", "c")
       h.should eq({"a" => 3, "b" => 6, "c" => 9})
     end
   end
@@ -1282,7 +1282,7 @@ describe "Hash" do
     it { {"a" => 2, "b" => 3}.select(Set{"b", "a"}).should eq({"a" => 2, "b" => 3}) }
     it "does not change current hash" do
       h = {"a" => 3, "b" => 6, "c" => 9}
-      h2 = h.select("b", "c")
+      h.select("b", "c")
       h.should eq({"a" => 3, "b" => 6, "c" => 9})
     end
   end

spec/std/http/client/client_spec.cr

@@ -240,7 +240,6 @@ module HTTP
 
     it "will not retry when closed (non-block) (#12464)" do
       requests = 0
-      server_channel = Channel(Nil).new
 
       client = HTTP::Client.new("127.0.0.1", 0)
       client.before_request do
@@ -256,7 +255,6 @@ module HTTP
 
     it "will not retry when closed (block) (#12464)" do
       requests = 0
-      server_channel = Channel(Nil).new
 
       client = HTTP::Client.new("127.0.0.1", 0)
       client.before_request do

spec/std/http/headers_spec.cr

@@ -20,7 +20,7 @@ describe HTTP::Headers do
 
   it "raises an error if header value contains invalid character" do
     expect_raises ArgumentError do
-      headers = HTTP::Headers{"invalid-header" => "\r\nLocation: http://example.com"}
+      HTTP::Headers{"invalid-header" => "\r\nLocation: http://example.com"}
     end
   end
 

spec/std/log/context_spec.cr

@@ -41,7 +41,7 @@ describe Log do
       Log.context.set a: 1
       done = Channel(Nil).new
 
-      f = spawn do
+      spawn do
         Log.context.metadata.should eq(Log::Metadata.new)
         Log.context.set b: 2
         Log.context.metadata.should eq(m({b: 2}))

spec/std/log/dispatch_spec.cr

@@ -15,7 +15,7 @@ class Log
     it "dispatches entry" do
       backend = Log::MemoryBackend.new
       backend.dispatcher = DirectDispatcher
-      backend.dispatch entry = Entry.new("source", :info, "message", Log::Metadata.empty, nil)
+      backend.dispatch Entry.new("source", :info, "message", Log::Metadata.empty, nil)
       backend.entries.size.should eq(1)
     end
   end
@@ -24,7 +24,7 @@ class Log
     it "dispatches entry" do
       backend = Log::MemoryBackend.new
       backend.dispatcher = SyncDispatcher.new
-      backend.dispatch entry = Entry.new("source", :info, "message", Log::Metadata.empty, nil)
+      backend.dispatch Entry.new("source", :info, "message", Log::Metadata.empty, nil)
       backend.entries.size.should eq(1)
     end
   end
@@ -33,22 +33,22 @@ class Log
     it "dispatches entry" do
       backend = Log::MemoryBackend.new
       backend.dispatcher = AsyncDispatcher.new
-      backend.dispatch entry = Entry.new("source", :info, "message", Log::Metadata.empty, nil)
+      backend.dispatch Entry.new("source", :info, "message", Log::Metadata.empty, nil)
       retry { backend.entries.size.should eq(1) }
     end
 
     it "wait for entries to flush before closing" do
       backend = Log::MemoryBackend.new
       backend.dispatcher = AsyncDispatcher.new
-      backend.dispatch entry = Entry.new("source", :info, "message", Log::Metadata.empty, nil)
+      backend.dispatch Entry.new("source", :info, "message", Log::Metadata.empty, nil)
       backend.close
       backend.entries.size.should eq(1)
     end
 
     it "can be closed twice" do
       backend = Log::MemoryBackend.new
       backend.dispatcher = AsyncDispatcher.new
-      backend.dispatch entry = Entry.new("source", :info, "message", Log::Metadata.empty, nil)
+      backend.dispatch Entry.new("source", :info, "message", Log::Metadata.empty, nil)
       backend.close
       backend.close
       backend.entries.size.should eq(1)

spec/std/oauth2/session_spec.cr

@@ -5,8 +5,8 @@ module OAuth2
   typeof(begin
     client = Client.new "localhost", "client_id", "client_secret", redirect_uri: "uri", authorize_uri: "/baz"
     token = OAuth2::AccessToken::Bearer.new("token", 3600)
-    session = Session.new(client, token) { |s| }
-    session = Session.new(client, token, Time.utc) { |s| }
+    session = Session.new(client, token) { |_| }
+    session = Session.new(client, token, Time.utc) { |_| }
     session.authenticate(HTTP::Client.new("localhost"))
   end)
 end

spec/std/proc_spec.cr

@@ -17,13 +17,11 @@ describe "Proc" do
   end
 
   it "does to_s" do
-    str = IO::Memory.new
     f = ->(x : Int32) { x.to_f }
     f.to_s.should eq("#<Proc(Int32, Float64):0x#{f.pointer.address.to_s(16)}>")
   end
 
   it "does to_s when closured" do
-    str = IO::Memory.new
     a = 1.5
     f = ->(x : Int32) { x + a }
     f.to_s.should eq("#<Proc(Int32, Float64):0x#{f.pointer.address.to_s(16)}:closure>")

spec/std/socket/tcp_socket_spec.cr

@@ -58,7 +58,7 @@ describe TCPSocket, tags: "network" do
 
         TCPServer.open("localhost", port) do |server|
           TCPSocket.open("localhost", port) do |client|
-            sock = server.accept
+            server.accept
           end
         end
       end

spec/std/string_spec.cr

@@ -1332,7 +1332,7 @@ describe "String" do
     end
 
     it "subs char with string" do
-      replaced = "foobar".sub do |char|
+      "foobar".sub do |char|
         char.should eq 'f'
         "some"
       end.should eq("someoobar")

src/compiler/crystal/codegen/codegen.cr

@@ -1499,7 +1499,6 @@ module Crystal
       end
 
       # First accept all yield expressions and assign them to block vars
-      i = 0
       unless node.exps.empty?
         exp_values = Array({LLVM::Value, Type}).new(node.exps.size)
 

src/compiler/crystal/codegen/fun.cr

@@ -38,8 +38,6 @@ class Crystal::CodeGenVisitor
       func.varargs?
     )
 
-    p2 = new_fun.params.to_a
-
     func.params.to_a.each_with_index do |p1, index|
       attrs = new_fun.attributes(index + 1)
       new_fun.add_attribute(attrs, index + 1) unless attrs.value == 0
@@ -125,7 +123,6 @@ class Crystal::CodeGenVisitor
 
         if @debug.variables? && !target_def.naked?
           in_alloca_block do
-            args_offset = !is_fun_literal && self_type.passed_as_self? ? 2 : 1
             location = target_def.location
             context.vars.each do |name, var|
               next if var.debug_variable_created

src/compiler/crystal/codegen/primitives.cr

@@ -748,7 +748,7 @@ class Crystal::CodeGenVisitor
 
     old_debug_location = @current_debug_location
     if @debug.line_numbers? && (location = node.location)
-      set_current_debug_location(node.location)
+      set_current_debug_location(location)
     end
 
     if type.element_type.has_inner_pointers?

src/compiler/crystal/command.cr

@@ -210,7 +210,7 @@ class Crystal::Command
 
     output_filename = Crystal.temp_executable(config.output_filename)
 
-    result = config.compile output_filename
+    config.compile output_filename
 
     unless config.compiler.no_codegen?
       report_warnings