Revert "Enhanced RDoc for Integer (#5099)"

This reverts commit fc456adc6a62d09b755243b8c8f190934b9965d6.

It broke the CI check.

https://github.com/ruby/ruby/runs/4207922247?check_suite_focus=true#step:3:4
```
numeric.c:3518: *     255.chr(Encoding::UTF_8) # => "ÿ"
Error: Process completed with exit code 1.
```

1 files changed, 69 insertions, 138 deletions

diff --git a/numeric.c b/numeric.c
index 224232f603..7a28e32b27 100644
--- a/numeric.c
+++ b/numeric.c
@@ -3338,25 +3338,9 @@ rb_int_even_p(VALUE num)
 
 /*
  *  call-seq:
- *    allbits?(mask) -> true or false
- *
- *  Returns +true+ if all bits that are set (=1) in +mask+
- *  are also set in +self+; returns +false+ otherwise.
- *
- *  Example values:
- *
- *    0b1010101  self
- *    0b1010100  mask
- *    0b1010100  self & mask
- *         true  self.allbits?(mask)
- *
- *    0b1010100  self
- *    0b1010101  mask
- *    0b1010100  self & mask
- *        false  self.allbits?(mask)
- *
- *  Related: Integer#anybits?, Integer#nobits?.
+ *     int.allbits?(mask)  ->  true or false
  *
+ *  Returns +true+ if all bits of <code>+int+ & +mask+</code> are 1.
  */
 
 static VALUE
@@ -3368,25 +3352,9 @@ int_allbits_p(VALUE num, VALUE mask)
 
 /*
  *  call-seq:
- *    anybits?(mask) -> true or false
- *
- *  Returns +true+ if any bit that is set (=1) in +mask+
- *  is also set in +self+; returns +false+ otherwise.
- *
- *  Example values:
- *
- *    0b10000010  self
- *    0b11111111  mask
- *    0b10000010  self & mask
- *          true  self.anybits?(mask)
- *
- *    0b00000000  self
- *    0b11111111  mask
- *    0b00000000  self & mask
- *         false  self.anybits?(mask)
- *
- *  Related: Integer#allbits?, Integer#nobits?.
+ *     int.anybits?(mask)  ->  true or false
  *
+ *  Returns +true+ if any bits of <code>+int+ & +mask+</code> are 1.
  */
 
 static VALUE
@@ -3398,25 +3366,9 @@ int_anybits_p(VALUE num, VALUE mask)
 
 /*
  *  call-seq:
- *    nobits?(mask) -> true or false
- *
- *  Returns +true+ if no bit that is set (=1) in +mask+
- *  is also set in +self+; returns +false+ otherwise.
- *
- *  Example values:
- *
- *    0b11110000  self
- *    0b00001111  mask
- *    0b00000000  self & mask
- *          true  self.nobits?(mask)
- *
- *    0b00000001  self
- *    0b11111111  mask
- *    0b00000001  self & mask
- *         false  self.nobits?(mask)
- *
- *  Related: Integer#allbits?, Integer#anybits?.
+ *     int.nobits?(mask)  ->  true or false
  *
+ *  Returns +true+ if no bits of <code>+int+ & +mask+</code> are 1.
  */
 
 static VALUE
@@ -3427,17 +3379,19 @@ int_nobits_p(VALUE num, VALUE mask)
 }
 
 /*
+ *  Document-method: Integer#succ
+ *  Document-method: Integer#next
  *  call-seq:
- *    succ -> next_integer
+ *     int.next  ->  integer
+ *     int.succ  ->  integer
  *
- *  Returns the successor integer of +self+ (equivalent to <tt>self + 1</tt>):
+ *  Returns the successor of +int+,
+ *  i.e. the Integer equal to <code>int+1</code>.
  *
- *    1.succ  #=> 2
- *    -1.succ #=> 0
- *
- *  Integer#next is an alias for Integer#succ.
- *
- *  Related: Integer#pred (predecessor value).
+ *     1.next      #=> 2
+ *     (-1).next   #=> 0
+ *     1.succ      #=> 2
+ *     (-1).succ   #=> 0
  */
 
 VALUE
@@ -3457,15 +3411,13 @@ rb_int_succ(VALUE num)
 
 /*
  *  call-seq:
- *    pred -> next_integer
- *
- *  Returns the predecessor of +self+ (equivalent to <tt>self - 1</tt>):
- *
- *    1.pred  #=> 0
- *    -1.pred #=> -2
+ *     int.pred  ->  integer
  *
- *  Related: Integer#succ (successor value).
+ *  Returns the predecessor of +int+,
+ *  i.e. the Integer equal to <code>int-1</code>.
  *
+ *     1.pred      #=> 0
+ *     (-1).pred   #=> -2
  */
 
 static VALUE
@@ -3483,6 +3435,19 @@ rb_int_pred(VALUE num)
 
 #define int_pred rb_int_pred
 
+/*
+ *  Document-method: Integer#chr
+ *  call-seq:
+ *     int.chr([encoding])  ->  string
+ *
+ *  Returns a string containing the character represented by the +int+'s value
+ *  according to +encoding+.
+ *
+ *     65.chr    #=> "A"
+ *     230.chr   #=> "\xE6"
+ *     255.chr(Encoding::UTF_8)   #=> "\u00FF"
+ */
+
 VALUE
 rb_enc_uint_chr(unsigned int code, rb_encoding *enc)
 {
@@ -3505,24 +3470,6 @@ rb_enc_uint_chr(unsigned int code, rb_encoding *enc)
     return str;
 }
 
-/*
- *  call-seq:
- *    chr(encoding = Encoding.default_internal) -> string
- *
- *  Returns a 1-character string containing the character
- *  represented by the value of +self+, according to the given +encoding+.
- *
- *     65.chr                   # => "A"
- *     0..chr                   # => "\x00"
- *     255.chr                  # => "\xFF"
- *     255.chr(Encoding::UTF_8) # => "ÿ"
- *
- *  Raises an exception if +self+ is negative.
- *
- *  Related: Integer#ord.
- *
- */
-
 static VALUE
 int_chr(int argc, VALUE *argv, VALUE num)
 {
@@ -3588,6 +3535,23 @@ rb_int_uminus(VALUE num)
     }
 }
 
+/*
+ *  Document-method: Integer#to_s
+ *  call-seq:
+ *     int.to_s(base=10)  ->  string
+ *
+ *  Returns a string containing the place-value representation of +int+
+ *  with radix +base+ (between 2 and 36).
+ *
+ *     12345.to_s       #=> "12345"
+ *     12345.to_s(2)    #=> "11000000111001"
+ *     12345.to_s(8)    #=> "30071"
+ *     12345.to_s(10)   #=> "12345"
+ *     12345.to_s(16)   #=> "3039"
+ *     12345.to_s(36)   #=> "9ix"
+ *     78546939656932.to_s(36)  #=> "rubyrules"
+ */
+
 VALUE
 rb_fix2str(VALUE x, int base)
 {
@@ -3630,27 +3594,6 @@ rb_fix2str(VALUE x, int base)
     return rb_usascii_str_new(b, e - b);
 }
 
-/*
- *  call-seq:
- *    to_s(base = 10)  ->  string
- *
- *  Returns a string containing the place-value representation of +self+
- *  in radix +base+ (in 2..36).
- *
- *    12345.to_s               # => "12345"
- *    12345.to_s(2)            # => "11000000111001"
- *    12345.to_s(8)            # => "30071"
- *    12345.to_s(10)           # => "12345"
- *    12345.to_s(16)           # => "3039"
- *    12345.to_s(36)           # => "9ix"
- *    78546939656932.to_s(36)  # => "rubyrules"
- *
- *  Raises an exception if +base+ is out of range.
- *
- *  Integer#inspect is an alias for Integer#to_s.
- *
- */
-
 static VALUE
 int_to_s(int argc, VALUE *argv, VALUE x)
 {
@@ -3676,6 +3619,15 @@ rb_int2str(VALUE x, int base)
     return rb_any_to_s(x);
 }
 
+/*
+ * Document-method: Integer#+
+ * call-seq:
+ *    int + numeric  ->  numeric_result
+ *
+ * Performs addition: the class of the resulting object depends on
+ * the class of +numeric+.
+ */
+
 static VALUE
 fix_plus(VALUE x, VALUE y)
 {
@@ -3702,21 +3654,6 @@ rb_fix_plus(VALUE x, VALUE y)
     return fix_plus(x, y);
 }
 
-/*
- *  call-seq:
- *    self + numeric -> numeric
- *
- *  Performs addition:
- *
- *    2 + 2              # => 4
- *    -2 + 2             # => 0
- *    -2 + -2            # => -4
- *    2 + 2.0            # => 4.0
- *    2 + Rational(2, 1) # => (4/1)
- *    2 + Complex(2, 0)  # => (4+0i)
- *
- */
-
 VALUE
 rb_int_plus(VALUE x, VALUE y)
 {
@@ -3729,6 +3666,15 @@ rb_int_plus(VALUE x, VALUE y)
     return rb_num_coerce_bin(x, y, '+');
 }
 
+/*
+ * Document-method: Integer#-
+ * call-seq:
+ *    int - numeric  ->  numeric_result
+ *
+ * Performs subtraction: the class of the resulting object depends on
+ * the class of +numeric+.
+ */
+
 static VALUE
 fix_minus(VALUE x, VALUE y)
 {
@@ -3747,21 +3693,6 @@ fix_minus(VALUE x, VALUE y)
     }
 }
 
-/*
- *  call-seq:
- *    int - numeric -> numeric
- *
- *  Performs subtraction:
- *
- *    4 - 2              # => 2
- *    -4 - 2             # => -6
- *    -4 - -2            # => -2
- *    4 - 2.0            # => 2.0
- *    4 - Rational(2, 1) # => (2/1)
- *    4 - Complex(2, 0)  # => (2+0i)
- *
- */
-
 VALUE
 rb_int_minus(VALUE x, VALUE y)
 {