32 files changed, 2312 insertions, 1114 deletions

diff --git a/.github/workflows/auto_request_review.yml b/.github/workflows/auto_request_review.yml
index 6d8edd5c22..f837905fe6 100644
--- a/.github/workflows/auto_request_review.yml
+++ b/.github/workflows/auto_request_review.yml
@@ -10,6 +10,7 @@ jobs:
   auto-request-review:
     name: Auto Request Review
     runs-on: ubuntu-latest
+    if: ${{ github.repository == 'ruby/ruby' }}
     steps:
       - name: Request review based on files changes and/or groups the author belongs to
         uses: necojackarc/auto-request-review@b5e81876454003a4ccb9b89cb205c67d77d7035b # v0.8.0
diff --git a/.github/workflows/cirrus-notify.yml b/.github/workflows/cirrus-notify.yml
index c78f21d258..5edba0ae8f 100644
--- a/.github/workflows/cirrus-notify.yml
+++ b/.github/workflows/cirrus-notify.yml
@@ -17,7 +17,7 @@ jobs:
       && github.event.check_suite.head_branch == 'master'
     runs-on: ubuntu-latest
     steps:
-      - uses: octokit/request-action@4579f9e1e690974421f9f6928a30fb448e967c60 # v2.x
+      - uses: octokit/request-action@52ce92ce3185e00e2425f043c3e9509121929aea # v2.x
         id: get_failed_check_run
         with:
           route: GET /repos/${{ github.repository }}/check-suites/${{ github.event.check_suite.id }}/check-runs?status=completed
diff --git a/NEWS.md b/NEWS.md
index 3c287f022a..d9d180f95b 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -327,7 +327,7 @@ Note: We're only listing outstanding class updates.
 * String
 
     * String#byteindex and String#byterindex have been added. [[Feature #13110]]
-    * Update Unicode to Version 14.0.0 and Emoji Version 14.0. [[Feature #18037]]
+    * Update Unicode to Version 15.0.0 and Emoji Version 15.0. [[Feature #18639]]
       (also applies to Regexp)
     * String#bytesplice has been added.  [[Feature #18598]]
 
@@ -372,11 +372,12 @@ Note: We're only listing outstanding class updates.
 
     * RubyGems 3.4.0.dev
     * benchmark 0.2.1
-    * bigdecimal 3.1.2
+    * bigdecimal 3.1.3
     * bundler 2.4.0.dev
     * cgi 0.3.6
     * date 3.3.0
     * delegate 0.3.0
+    * did_you_mean 1.6.2
     * digest 3.1.1
     * drb 2.1.1
     * erb 4.0.2
@@ -415,6 +416,12 @@ Note: We're only listing outstanding class updates.
     * stringio 3.0.3
     * syntax_suggest 1.0.1
     * timeout 0.3.1
+    * tmpdir 0.1.3
+    * tsort 0.1.1
+    * un 0.2.1
+    * uri 0.12.0
+    * win32ole 1.8.9
+    * zlib 3.0.0
 
 *   The following bundled gems are updated.
 
@@ -549,20 +556,6 @@ The following deprecated APIs are removed.
 * Rename `--mjit-min-calls` to `--mjit-call-threshold`.
 * Change default `--mjit-max-cache` back from 10000 to 100.
 
-## Static analysis
-
-### RBS
-
-### TypeProf
-
-## Debugger
-
-## error_highlight
-
-## IRB Autocomplete and Document Display
-
-## Miscellaneous changes
-
 [Feature #12005]: https://bugs.ruby-lang.org/issues/12005
 [Feature #12084]: https://bugs.ruby-lang.org/issues/12084
 [Feature #12655]: https://bugs.ruby-lang.org/issues/12655
@@ -584,7 +577,6 @@ The following deprecated APIs are removed.
 [Bug #17545]:     https://bugs.ruby-lang.org/issues/17545
 [Feature #17837]: https://bugs.ruby-lang.org/issues/17837
 [Feature #17881]: https://bugs.ruby-lang.org/issues/17881
-[Feature #18037]: https://bugs.ruby-lang.org/issues/18037
 [Feature #18159]: https://bugs.ruby-lang.org/issues/18159
 [Feature #18351]: https://bugs.ruby-lang.org/issues/18351
 [Feature #18481]: https://bugs.ruby-lang.org/issues/18481
@@ -597,6 +589,7 @@ The following deprecated APIs are removed.
 [Bug #18625]:     https://bugs.ruby-lang.org/issues/18625
 [Feature #18630]: https://bugs.ruby-lang.org/issues/18630
 [Bug #18633]:     https://bugs.ruby-lang.org/issues/18633
+[Feature #18639]: https://bugs.ruby-lang.org/issues/18639
 [Feature #18685]: https://bugs.ruby-lang.org/issues/18685
 [Feature #18776]: https://bugs.ruby-lang.org/issues/18776
 [Bug #18782]:     https://bugs.ruby-lang.org/issues/18782
diff --git a/common.mk b/common.mk
index 9256214eed..182d1db920 100644
--- a/common.mk
+++ b/common.mk
@@ -18,7 +18,7 @@ mflags = $(MFLAGS)
 gnumake_recursive =
 enable_shared = $(ENABLE_SHARED:no=)
 
-UNICODE_VERSION = 14.0.0
+UNICODE_VERSION = 15.0.0
 UNICODE_EMOJI_VERSION_0 = $(UNICODE_VERSION)///
 UNICODE_EMOJI_VERSION_1 = $(UNICODE_EMOJI_VERSION_0:.0///=)
 UNICODE_EMOJI_VERSION = $(UNICODE_EMOJI_VERSION_1:///=)
@@ -873,7 +873,7 @@ extconf: $(PREP)
 rbconfig.rb: $(RBCONFIG)
 
 $(HAVE_BASERUBY:no=)$(RBCONFIG)$(HAVE_BASERUBY:no=): $(PREP)
-$(RBCONFIG): $(tooldir)/mkconfig.rb config.status $(srcdir)/version.h
+$(RBCONFIG): $(tooldir)/mkconfig.rb config.status $(srcdir)/version.h $(srcdir)/common.mk
 	$(Q)$(BOOTSTRAPRUBY) -n \
 	-e 'BEGIN{version=ARGV.shift;mis=ARGV.dup}' \
 	-e 'END{abort "UNICODE version mismatch: #{mis}" unless mis.empty?}' \
diff --git a/enc/unicode/14.0.0/casefold.h b/enc/unicode/15.0.0/casefold.h
index d387cff628..51120d867d 100644
--- a/enc/unicode/14.0.0/casefold.h
+++ b/enc/unicode/15.0.0/casefold.h
@@ -1,15 +1,15 @@
 /* DO NOT EDIT THIS FILE. */
-/* Generated by enc/unicode/case-folding.rb */
+/* Generated by enc-case-folding.rb */
 
 #if defined ONIG_UNICODE_VERSION_STRING && !( \
-      ONIG_UNICODE_VERSION_MAJOR == 14 && \
+      ONIG_UNICODE_VERSION_MAJOR == 15 && \
       ONIG_UNICODE_VERSION_MINOR == 0 && \
       ONIG_UNICODE_VERSION_TEENY == 0 && \
       1)
 # error ONIG_UNICODE_VERSION_STRING mismatch
 #endif
-#define ONIG_UNICODE_VERSION_STRING "14.0.0"
-#define ONIG_UNICODE_VERSION_MAJOR 14
+#define ONIG_UNICODE_VERSION_STRING "15.0.0"
+#define ONIG_UNICODE_VERSION_MAJOR 15
 #define ONIG_UNICODE_VERSION_MINOR 0
 #define ONIG_UNICODE_VERSION_TEENY 0
 
diff --git a/enc/unicode/14.0.0/name2ctype.h b/enc/unicode/15.0.0/name2ctype.h
index 61c16bafc2..a2c996423d 100644
--- a/enc/unicode/14.0.0/name2ctype.h
+++ b/enc/unicode/15.0.0/name2ctype.h