Fix or revert some return type restrictions from #10575

src/digest/io_digest.cr

@@ -30,7 +30,7 @@ class IO::Digest < IO
   def initialize(@io : IO, @digest_algorithm : ::Digest, @mode = DigestMode::Read)
   end
 
-  def read(slice : Bytes) : Int32
+  def read(slice : Bytes)
     read_bytes = io.read(slice)
     if @mode.read?
       digest_algorithm.update(slice[0, read_bytes])

src/enumerable.cr

@@ -238,7 +238,7 @@ module Enumerable(T)
   # ```
   # [1, 2, 3, 4].count { |i| i % 2 == 0 } # => 2
   # ```
-  def count
+  def count(& : T -> _) : Int32
     count = 0
     each { |e| count += 1 if yield e }
     count
@@ -624,7 +624,7 @@ module Enumerable(T)
   # ```
   #
   # Returns `nil` if the block didn't return `true` for any element.
-  def index
+  def index(& : T -> _) : Int32?
     each_with_index do |e, i|
       return i if yield e
     end
@@ -638,7 +638,7 @@ module Enumerable(T)
   # ```
   #
   # Returns `nil` if *obj* is not in the collection.
-  def index(obj)
+  def index(obj) : Int32?
     index { |e| e == obj }
   end
 

src/http/content.cr

@@ -26,7 +26,7 @@ module HTTP
   class FixedLengthContent < IO::Sized
     include Content
 
-    def read(slice : Bytes) : Int32
+    def read(slice : Bytes)
       ensure_send_continue
       super
     end
@@ -58,7 +58,7 @@ module HTTP
     def initialize(@io : IO)
     end
 
-    def read(slice : Bytes) : Int32
+    def read(slice : Bytes)
       ensure_send_continue
       @io.read(slice)
     end
@@ -73,7 +73,7 @@ module HTTP
       @io.peek
     end
 
-    def skip(bytes_count) : Int32?
+    def skip(bytes_count) : Nil
       ensure_send_continue
       @io.skip(bytes_count)
     end
@@ -112,7 +112,7 @@ module HTTP
       @received_final_chunk = false
     end
 
-    def read(slice : Bytes) : Int32
+    def read(slice : Bytes)
       ensure_send_continue
       count = slice.size
       return 0 if count == 0
@@ -164,7 +164,7 @@ module HTTP
       peek
     end
 
-    def skip(bytes_count) : Int32?
+    def skip(bytes_count) : Nil
       ensure_send_continue
       if bytes_count <= @chunk_remaining
         @io.skip(bytes_count)

src/humanize.cr

@@ -82,7 +82,7 @@ struct Number
   end
 
   # :nodoc:
-  def self.prefix_index(i, group = 3) : Int32
+  def self.prefix_index(i : Int32, group : Int32 = 3) : Int32
     ((i - (i > 0 ? 1 : 0)) // group) * group
   end
 

src/io/argf.cr

@@ -10,7 +10,7 @@ class IO::ARGF < IO
     @read_from_stdin = false
   end
 
-  def read(slice : Bytes) : Int32
+  def read(slice : Bytes)
     first_initialize unless @initialized
 
     if current_io = @current_io

src/io/hexdump.cr

@@ -26,7 +26,7 @@ class IO::Hexdump < IO
   def initialize(@io : IO, @output : IO = STDERR, @read = false, @write = false)
   end
 
-  def read(buf : Bytes) : Int32
+  def read(buf : Bytes)
     @io.read(buf).tap do |read_bytes|
       buf[0, read_bytes].hexdump(@output) if @read && read_bytes
     end

src/io/memory.cr

@@ -192,7 +192,7 @@ class IO::Memory < IO
   end
 
   # :nodoc:
-  def skip(bytes_count)
+  def skip(bytes_count) : Nil
     check_open
 
     available = @bytesize - @pos

src/io/sized.cr

@@ -25,7 +25,7 @@ class IO::Sized < IO
     @read_remaining = read_size.to_u64
   end
 
-  def read(slice : Bytes) : Int32
+  def read(slice : Bytes)
     check_open
 
     count = {slice.size.to_u64, @read_remaining}.min

src/io/stapled.cr

@@ -30,7 +30,7 @@ class IO::Stapled < IO
   end
 
   # Reads a slice from `reader`.
-  def read(slice : Bytes) : Int32
+  def read(slice : Bytes)
     check_open
 
     @reader.read(slice)

src/string.cr

@@ -817,7 +817,7 @@ class String
   # s[-2..-4] # => ""
   # s[-2..1]  # => ""
   # s[3..-4]  # => ""
-  # ``` : String
+  # ```
   def [](range : Range) : String
     self[*Indexable.range_to_index_and_count(range, size) || raise IndexError.new]
   end
@@ -5010,7 +5010,7 @@ class String
   # Raises an `ArgumentError` if `self` has null bytes. Returns `self` otherwise.
   #
   # This method should sometimes be called before passing a `String` to a C function.
-  def check_no_null_byte(name = nil) : String
+  def check_no_null_byte(name = nil) : self
     if byte_index(0)
       name = "`#{name}` " if name
       raise ArgumentError.new("String #{name}contains null byte")