From f772c9a9bed1af9448f1e8afa13a45e787f5d435 Mon Sep 17 00:00:00 2001
From: Chris Lamb <chris@chris-lamb.co.uk>
Date: Tue, 2 Jun 2020 15:17:23 +0100
Subject: [PATCH 1/2] Ensure default Set values are sorted for a reproducible
 build

Whilst working on the Reproducible Builds effort [0] we noticed
that traitlets generates non-reproducible output which is affecting
the reproducibility of other packages. For example, in nbconvert:

  -<dd><p class="first">Default: {'image/jpeg',</span> <span class="pre">'image/svg+xml',</span> [..]
  +<dd><p class="first">Default: {'image/svg+xml',</span> <span class="pre">'application/pdf',</span> [..]

(From https://tests.reproducible-builds.org/debian/rb-pkg/unstable/
amd64/nbconvert.html on 20191014)

This is due to it not iterating over a Set traitlet type in a
deterministic ordering when generating the "Default:" human-readable
string.

This patch ensures that we display the Set traits defaults in a
sorted, and thus reproducible, manner.

  [0] https://reproducible-builds.org/
---
 traitlets/traitlets.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/traitlets/traitlets.py b/traitlets/traitlets.py
index c53b934f..42cf4ef8 100644
--- a/traitlets/traitlets.py
+++ b/traitlets/traitlets.py
@@ -2596,6 +2596,10 @@ def __init__(self, trait=None, default_value=None, minlen=0, maxlen=sys.maxsize,
         """
         super(Set, self).__init__(trait, default_value, minlen, maxlen, **kwargs)
 
+    def default_value_repr(self):
+        # Ensure default value is sorted for a reproducible build
+        return repr(sorted(self.make_dynamic_default()))
+
 
 class Tuple(Container):
     """An instance of a Python tuple."""

From df72b2870b5c1f08d88106093d3a01476f84160e Mon Sep 17 00:00:00 2001
From: Matthias Bussonnier <bussonniermatthias@gmail.com>
Date: Tue, 11 Aug 2020 11:17:59 -0700
Subject: [PATCH 2/2] Ensure help is reproducible as well.

---
 traitlets/config/tests/test_configurable.py | 6 ++++++
 traitlets/traitlets.py                      | 5 ++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/traitlets/config/tests/test_configurable.py b/traitlets/config/tests/test_configurable.py
index 35f42f51..14d85f80 100644
--- a/traitlets/config/tests/test_configurable.py
+++ b/traitlets/config/tests/test_configurable.py
@@ -62,7 +62,9 @@ class Bar(Foo):
     b = Unicode('gotit', help="The string b.").tag(config=False)
     c = Float(help="The string c.").tag(config=True)
     bset = Set([]).tag(config=True, multiplicity='+')
+    bset_values = Set([2,1,5]).tag(config=True, multiplicity='+')
     bdict = Dict().tag(config=True, multiplicity='+')
+    bdict_values = Dict({1:'a','0':'b',5:'c'}).tag(config=True, multiplicity='+')
 
 foo_help=u"""Foo(Configurable) options
 -------------------------
@@ -83,8 +85,12 @@ class Bar(Foo):
     Default: 0
 --Bar.bdict <key-1>=<value-1>...
     Default: {}
+--Bar.bdict_values <key-1>=<value-1>...
+    Default: {1: 'a', '0': 'b', 5: 'c'}
 --Bar.bset <set-item-1>...
     Default: set()
+--Bar.bset_values <set-item-1>...
+    Default: {1, 2, 5}
 --Bar.c=<Float>
     The string c.
     Default: 0.0
diff --git a/traitlets/traitlets.py b/traitlets/traitlets.py
index 42cf4ef8..3c8629ff 100644
--- a/traitlets/traitlets.py
+++ b/traitlets/traitlets.py
@@ -2598,7 +2598,10 @@ def __init__(self, trait=None, default_value=None, minlen=0, maxlen=sys.maxsize,
 
     def default_value_repr(self):
         # Ensure default value is sorted for a reproducible build
-        return repr(sorted(self.make_dynamic_default()))
+        list_repr = repr(sorted(self.make_dynamic_default()))
+        if list_repr == '[]':
+            return 'set()'
+        return '{'+list_repr[1:-1]+'}'
 
 
 class Tuple(Container):