Add inspection of Regex options support

spec/std/regex_spec.cr

@@ -534,4 +534,14 @@ describe "Regex" do
       end
     )
   end
+
+  it ".supports_compile_options?" do
+    Regex.supports_compile_options?(:anchored).should be_true
+    Regex.supports_compile_options?(:endanchored).should eq Regex::Engine.version_number >= {10, 0}
+  end
+
+  it ".supports_match_options?" do
+    Regex.supports_compile_options?(:anchored).should be_true
+    Regex.supports_compile_options?(:endanchored).should eq Regex::Engine.version_number >= {10, 0}
+  end
 end

src/regex.cr

@@ -285,6 +285,14 @@ class Regex
   # This alias is supposed to replace `Options`.
   alias CompileOptions = Options
 
+  # Returns `true` if the regex engine supports all *options* flags when compiling a pattern.
+  def self.supports_compile_options?(options : CompileOptions) : Bool
+    options.each do |flag|
+      return false unless Engine.supports_compile_flag?(flag)
+    end
+    true
+  end
+
   # Represents options passed to regex match methods such as `Regex#match`.
   @[Flags]
   enum MatchOptions
@@ -308,6 +316,14 @@ class Regex
     NO_UTF_CHECK
   end
 
+  # Returns `true` if the regex engine supports all *options* flags when matching a pattern.
+  def self.supports_match_options?(options : MatchOptions) : Bool
+    options.each do |flag|
+      return false unless Engine.supports_match_flag?(flag)
+    end
+    true
+  end
+
   # Returns a `Regex::CompileOptions` representing the optional flags applied to this `Regex`.
   #
   # ```

src/regex/pcre.cr

@@ -61,6 +61,10 @@ module Regex::PCRE
     flag
   end
 
+  def self.supports_compile_flag?(options)
+    !options.endanchored? && !options.match_invalid_utf?
+  end
+
   private def pcre_match_options(options)
     flag = 0
     Regex::Options.each do |option|
@@ -113,6 +117,10 @@ module Regex::PCRE
     flag
   end
 
+  def self.supports_match_flag?(options)
+    !options.endanchored? && !options.no_jit?
+  end
+
   def finalize
     LibPCRE.free_study @extra
     {% unless flag?(:interpreted) %}

src/regex/pcre2.cr

@@ -90,6 +90,10 @@ module Regex::PCRE2
     flag
   end
 
+  def self.supports_compile_flag?(options)
+    true
+  end
+
   private def pcre2_match_options(options)
     flag = 0
     Regex::Options.each do |option|
@@ -140,6 +144,10 @@ module Regex::PCRE2
     flag
   end
 
+  def self.supports_match_flag?(options)
+    true
+  end
+
   protected def self.error_impl(source)
     code = PCRE2.compile(source, LibPCRE2::UTF | LibPCRE2::DUPNAMES | LibPCRE2::UCP) do |error_message|
       return error_message