cmake: Generate documentation.

To prevent complicating the dependencies of a core tool, a new variant,
CMAKE-MINIMAL is introduced and the CMake build system is configured to use it
by default.  The regular CMAKE package gains a manpage, info manual as well
as HTML documentation.

Fixes issue #33497 (https://bugs.gnu.org/33497).

* gnu/packages/cmake.scm (gnu): Use modules (gnu packages python-xyz),
(gnu packages texinfo) and (srfi srfi-1).
(cmake-minimal): Rename the original cmake variable to this.
[phases]{configure}: Extract the configure script arguments to...
[configure-flags]: here.
[properties]: Set the HIDDEN? property to #t.
(cmake): New variable, which inherits from CMAKE-MINIMAL.
[phases]{move-html-doc}: Add phase.
[native-inputs]: Add PYTHON-SPHINX and TEXINFO.
[outputs]: Add the "doc" output.
[properties]: Clear the inherited HIDDEN? property.
* guix/build-system/cmake.scm (default-cmake): Use CMAKE-MINIMAL instead of
CMAKE.

2 files changed, 70 insertions, 26 deletions

diff --git a/gnu/packages/cmake.scm b/gnu/packages/cmake.scm
index 7772fbedb1..b999c0c170 100644
--- a/gnu/packages/cmake.scm
+++ b/gnu/packages/cmake.scm
@@ -8,6 +8,8 @@
 ;;; Copyright © 2017, 2018 Marius Bakke <mbakke@fastmail.com>
 ;;; Copyright © 2018 Arun Isaac <arunisaac@systemreboot.net>
 ;;; Copyright © 2018 Tobias Geerinckx-Rice <me@tobias.gr>
+;;; Copyright © 2019 Maxim Cournoyer <maxim.cournoyer@gmail.com>
+
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -39,11 +41,16 @@
   #:use-module (gnu packages file)
   #:use-module (gnu packages libevent)
   #:use-module (gnu packages ncurses)
-  #:use-module (gnu packages xml))
+  #:use-module (gnu packages python-xyz)
+  #:use-module (gnu packages texinfo)
+  #:use-module (gnu packages xml)
+  #:use-module (srfi srfi-1))
 
-(define-public cmake
+;;; This minimal variant of CMake does not include the documentation. It is
+;;; used by the cmake-build-system.
+(define-public cmake-minimal
   (package
-    (name "cmake")
+    (name "cmake-minimal")
     (version "3.14.0")
     (source (origin
               (method url-fetch)
@@ -72,6 +79,23 @@
     (build-system gnu-build-system)
     (arguments
      `(#:test-target "test"
+       #:configure-flags
+       (let ((out (assoc-ref %outputs "out"))
+             (parallel-job-count (number->string (parallel-job-count))))
+         (list "--verbose"
+               (string-append "--parallel=" parallel-job-count)
+               (string-append "--prefix=" out)
+               "--system-libs"
+               "--no-system-jsoncpp"    ; FIXME: Circular dependency.
+               ;; By default, the man pages and other docs land
+               ;; in PREFIX/man and PREFIX/doc, but we want them
+               ;; in share/{man,doc}.  Note that unlike
+               ;; autoconf-generated configure scripts, cmake's
+               ;; configure prepends "PREFIX/" to what we pass
+               ;; to --mandir and --docdir.
+               "--mandir=share/man"
+               ,(string-append "--docdir=share/doc/cmake-"
+                               (version-major+minor version))))
        #:make-flags
        (let ((skipped-tests
               (list "BundleUtilities" ; This test fails on Guix.
@@ -119,25 +143,10 @@
                (setenv "CMAKE_INCLUDE_PATH" (or (getenv "CPATH")
                                                 (getenv "C_INCLUDE_PATH")))
                #t)))
+         ;; CMake uses its own configure script.
          (replace 'configure
-           (lambda* (#:key outputs #:allow-other-keys)
-             (let ((out (assoc-ref outputs "out")))
-               (invoke
-                "./configure" "--verbose"
-                (string-append "--parallel=" (number->string (parallel-job-count)))
-                (string-append "--prefix=" out)
-                "--system-libs"
-                "--no-system-jsoncpp" ; FIXME: Circular dependency.
-                ;; By default, the man pages and other docs land
-                ;; in PREFIX/man and PREFIX/doc, but we want them
-                ;; in share/{man,doc}.  Note that unlike
-                ;; autoconf-generated configure scripts, cmake's
-                ;; configure prepends "PREFIX/" to what we pass
-                ;; to --mandir and --docdir.
-                "--mandir=share/man"
-                ,(string-append
-                  "--docdir=share/doc/cmake-"
-                  (version-major+minor version)))))))))
+           (lambda* (#:key (configure-flags '()) #:allow-other-keys)
+             (apply invoke "./configure" configure-flags))))))
     (inputs
      `(("bzip2" ,bzip2)
        ("curl" ,curl)
@@ -159,12 +168,47 @@
 CMake is used to control the software compilation process using simple platform
 and compiler independent configuration files.  CMake generates native makefiles
 and workspaces that can be used in the compiler environment of your choice.")
-    (license (list license:bsd-3             ; cmake
-                   license:bsd-4             ; cmcompress
-                   license:bsd-2             ; cmlibarchive
-                   license:expat             ; cmjsoncpp is dual MIT/public domain
+    (properties '((hidden? . #t)))
+    (license (list license:bsd-3        ; cmake
+                   license:bsd-4        ; cmcompress
+                   license:bsd-2        ; cmlibarchive
+                   license:expat        ; cmjsoncpp is dual MIT/public domain
                    license:public-domain)))) ; cmlibarchive/archive_getdate.c
 
+(define-public cmake
+  (package
+    (inherit cmake-minimal)
+    (name "cmake")
+    (arguments
+     (substitute-keyword-arguments (package-arguments cmake-minimal)
+       ((#:configure-flags configure-flags ''())
+        `(append ,configure-flags
+                ;; Extra configure flags used to generate the documentation.
+                '("--sphinx-info"
+                  "--sphinx-man"
+                  "--sphinx-html")))
+       ((#:phases phases)
+        `(modify-phases ,phases
+           (add-after 'install 'move-html-doc
+             (lambda* (#:key outputs #:allow-other-keys)
+               (let ((out (assoc-ref outputs "out"))
+                     (doc (assoc-ref outputs "doc"))
+                     (html (string-append "/share/doc/cmake-"
+                                          ,(version-major+minor
+                                            (package-version cmake-minimal))
+                                          "/html")))
+                 (copy-recursively (string-append out html)
+                                   (string-append doc html))
+                 (delete-file-recursively (string-append out html))
+                 #t)))))))
+    ;; Extra inputs required to build the documentation.
+    (native-inputs
+     `(,@(package-native-inputs cmake-minimal)
+       ("python-sphinx" ,python-sphinx)
+       ("texinfo" ,texinfo)))
+    (outputs '("out" "doc"))
+    (properties (alist-delete 'hidden? (package-properties cmake-minimal)))))
+
 (define-public emacs-cmake-mode
   (package
     (inherit cmake)
diff --git a/guix/build-system/cmake.scm b/guix/build-system/cmake.scm
index ee116c5a4c..ca88fadddf 100644
--- a/guix/build-system/cmake.scm
+++ b/guix/build-system/cmake.scm
@@ -48,7 +48,7 @@
 
   ;; Do not use `@' to avoid introducing circular dependencies.
   (let ((module (resolve-interface '(gnu packages cmake))))
-    (module-ref module 'cmake)))
+    (module-ref module 'cmake-minimal)))
 
 (define* (lower name
                 #:key source inputs native-inputs outputs system target