[elpa] master 86fc109: update stream.el to the latest version

[Nicolas Petton]

branch: master
commit 86fc10993a4f2be9f13a229f7f6a27f2192cfff9
Author: Nicolas Petton <address@hidden>
Commit: Nicolas Petton <address@hidden>

    update stream.el to the latest version
    
    * packages/stream/stream.el:
    * packages/stream/tests/stream-tests.el: Add latest changes from the
      github repository.
---
 packages/stream/stream.el             |   30 +++++++++++++++++++++++++-
 packages/stream/tests/stream-tests.el |   37 +++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+), 1 deletions(-)

diff --git a/packages/stream/stream.el b/packages/stream/stream.el
index b03aa8a..567a9e3 100644
--- a/packages/stream/stream.el
+++ b/packages/stream/stream.el
@@ -113,6 +113,17 @@ The sequence starts at POS if non-nil, 1 otherwise."
            (char-after (point)))))
      (stream buffer (1+ pos)))))
 
+(declare-function iter-next "generator")
+
+(defun stream-from-iterator (iterator)
+  "Return a stream generating new elements through ITERATOR.
+ITERATOR is an iterator object in terms of the \"generator\"
+package."
+  (stream-make
+   (condition-case nil
+       (cons (iter-next iterator) (stream-from-iterator iterator))
+     (iter-end-of-sequence nil))))
+
 (defun stream-regexp (buffer regexp)
   (stream-make
    (let (match)
@@ -137,7 +148,8 @@ range is infinite."
 
 (defun streamp (stream)
   "Return non-nil if STREAM is a stream, nil otherwise."
-  (eq (car-safe stream) stream--identifier))
+  (and (consp stream)
+       (eq (car stream) stream--identifier)))
 
 (defun stream-empty ()
   "Return an empty stream."
@@ -156,6 +168,22 @@ range is infinite."
   (or (cdr (thunk-force (cadr stream)))
       (stream-empty)))
 
+(defun stream-append (&rest streams)
+  "Concatenate the STREAMS.
+Requesting elements from the resulting stream will request the
+elements in the STREAMS in order."
+  (if (null streams)
+      (stream-empty)
+    (stream-make
+     (let ((first (pop streams)))
+       (while (and (stream-empty-p first) streams)
+         (setq first (pop streams)))
+       (if (stream-empty-p first)
+           nil
+         (cons (stream-first first)
+               (if streams (apply #'stream-append (stream-rest first) streams)
+                 (stream-rest first))))))))
+
 (defmacro stream-pop (stream)
   "Return the first element of STREAM and set the value of STREAM to its rest."
   (unless (symbolp stream)
diff --git a/packages/stream/tests/stream-tests.el 
b/packages/stream/tests/stream-tests.el
index 1997202..88edf91 100644
--- a/packages/stream/tests/stream-tests.el
+++ b/packages/stream/tests/stream-tests.el
@@ -52,6 +52,35 @@
   (should (= 4 (stream-first (stream-rest (stream-range 3)))))
   (should (= 5 (stream-first (stream-rest (stream-rest (stream-range 3)))))))
 
+(ert-deftest stream-from-iterator-test ()
+  (skip-unless (require 'generator nil t))
+  (should (equal '(1 2)
+                 (seq-into-sequence
+                  (stream-from-iterator
+                   (funcall (iter-lambda ()
+                              (iter-yield 1)
+                              (iter-yield 2))))))))
+
+(ert-deftest stream-append-test ()
+  (should (stream-empty-p (stream-append)))
+  (should (let ((list '(1 2)))
+            (equal list (seq-into-sequence (stream-append (stream list))))))
+  (should (= (seq-elt (stream-append
+                       (stream (list 0 1))
+                       (stream-range 2))
+                      4)
+             4))
+  (should (let ((stream (stream (list 0))))
+            (and (= (seq-elt (stream-append stream (stream-range 1)) 10)
+                    10)
+                 (stream-empty-p (stream-rest stream)))))
+  (should (equal (seq-into-sequence
+                  (stream-append
+                   (stream '(1))
+                   (stream '())
+                   (stream '(2 3))))
+                 '(1 2 3))))
+
 (ert-deftest stream-seqp-test ()
   (should (seqp (stream-range))))
 
@@ -175,5 +204,13 @@
     (seq-map #'identity stream)
     (should-not consumed)))
 
+(ert-deftest stream-pop-test ()
+  (let* ((str (stream '(1 2 3)))
+         (first (stream-pop str))
+         (stream-empty (stream-empty)))
+    (should (= 1 first))
+    (should (= 2 (stream-first str)))
+    (should (null (stream-pop stream-empty)))))
+
 (provide 'stream-tests)
 ;;; stream-tests.el ends here