Fix bug#16826

* lisp/emacs-lisp/package.el (package-compute-transaction):
Use `version-list-<=' to compare the requirement version against
the package version already to be installed.  Update the error
message.

3 files changed, 32 insertions, 1 deletions

diff --git a/test/automated/data/package/archive-contents b/test/automated/data/package/archive-contents
index 8d6f3226ae6..a6df6b8086e 100644
--- a/test/automated/data/package/archive-contents
+++ b/test/automated/data/package/archive-contents
@@ -6,6 +6,10 @@
  (simple-depend .
                 [(1 0)
                  ((simple-single (1 3))) "A single-file package with a dependency." single])
+ (simple-two-depend .
+                [(1 1)
+                 ((simple-depend (1 0)) (simple-single (1 3)))
+                 "A single-file package with two dependencies." single])
  (multi-file .
              [(0 2 3)
               nil "Example of a multi-file tar package" tar
diff --git a/test/automated/data/package/simple-two-depend-1.1.el b/test/automated/data/package/simple-two-depend-1.1.el
new file mode 100644
index 00000000000..9cfe5c0d4e2
--- /dev/null
+++ b/test/automated/data/package/simple-two-depend-1.1.el
@@ -0,0 +1,17 @@
+;;; simple-two-depend.el --- A single-file package with two dependencies.
+
+;; Author: J. R. Hacker <jrh@example.com>
+;; Version: 1.1
+;; Keywords: frobnicate
+;; Package-Requires: ((simple-depend "1.0") (simple-single "1.3"))
+
+;;; Commentary:
+
+;; Depends on two another packages.
+
+;;; Code:
+
+(defvar simple-two-depend "Value"
+  "Some trivial code")
+
+;;; simple-two-depend.el ends here
diff --git a/test/automated/package-test.el b/test/automated/package-test.el
index 34a3ce25a48..72422a8684b 100644
--- a/test/automated/package-test.el
+++ b/test/automated/package-test.el
@@ -203,12 +203,22 @@ Must called from within a `tar-mode' buffer."
     (should (package-installed-p 'simple-single))
     (should (package-installed-p 'simple-depend))))
 
+(ert-deftest package-test-install-two-dependencies ()
+  "Install a package which includes a dependency."
+  (with-package-test ()
+    (package-initialize)
+    (package-refresh-contents)
+    (package-install 'simple-two-depend)
+    (should (package-installed-p 'simple-single))
+    (should (package-installed-p 'simple-depend))
+    (should (package-installed-p 'simple-two-depend))))
+
 (ert-deftest package-test-refresh-contents ()
   "Parse an \"archive-contents\" file."
   (with-package-test ()
     (package-initialize)
     (package-refresh-contents)
-    (should (eq 3 (length package-archive-contents)))))
+    (should (eq 4 (length package-archive-contents)))))
 
 (ert-deftest package-test-install-single-from-archive ()
   "Install a single package from a package archive."