Merge 16.4 maintenance branch into master

Author: tturocy

.github/workflows/lint.yml

@@ -9,7 +9,7 @@ jobs:
     name: clang-format
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Run clang-format style check for C/C++
         uses: jidicula/clang-format-action@v4.16.0
         with:
@@ -21,7 +21,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install dependencies
         run: |
           sudo apt-key adv --fetch-keys http://repos.codelite.org/CodeLite.asc
@@ -37,14 +37,14 @@ jobs:
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: chartboost/ruff-action@v1
 
   flake8:
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: actions/setup-python@v6
         with:
           python-version: "3.14"
@@ -54,7 +54,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Python
         uses: actions/setup-python@v6
         with:

.github/workflows/osxbinary.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: macos-14
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install dependencies
         run: |
             brew install automake autoconf

.github/workflows/python.yml

@@ -13,7 +13,7 @@ jobs:
         python-version: ['3.10', '3.14']
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v6
         with:
@@ -42,7 +42,7 @@ jobs:
         python-version: ['3.14']
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v6
         with:
@@ -67,7 +67,7 @@ jobs:
         python-version: ['3.14']
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v6
         with:
@@ -92,7 +92,7 @@ jobs:
         python-version: ['3.14']
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v6
         with:

.github/workflows/tools.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install dependencies
         run: |
           sudo apt-key adv --fetch-keys http://repos.codelite.org/CodeLite.asc
@@ -36,7 +36,7 @@ jobs:
     runs-on: macos-14
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install dependencies
         run: brew install automake autoconf wxwidgets
       - run: aclocal
@@ -55,7 +55,7 @@ jobs:
     runs-on: macos-15
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install dependencies
         run: brew install automake autoconf wxwidgets
       - run: aclocal
@@ -77,7 +77,7 @@ jobs:
       run:
         shell: msys2 {0}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: msys2/setup-msys2@v2
         with:
           install: mingw-w64-x86_64-toolchain make automake autoconf

.github/workflows/wheels.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: windows-latest
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python
         uses: actions/setup-python@v6
         with:

ChangeLog

@@ -30,7 +30,7 @@
   (and as a result from the `enumpure`, `lp`, and `lcp` command-line tools); this will be replaced
   with new and more customisable approaches. (#639)
 
-## [16.4.1] - unreleased
+## [16.4.1] - 2025-12-17
 
 ### Fixed
 - Fixed a regression in which null outcomes in strategic game tables were not handled correctly
@@ -45,7 +45,7 @@
   mixed behavior profiles (#616)
 
 
-## [16.3.2] - unreleased
+## [16.3.2] - 2025-12-04
 
 ### Fixed
 - Parsing of output of `gambit-logit` in the graphical interface did not handle the

doc/tools.gnm.rst

@@ -86,7 +86,6 @@ the reduced strategic form of the example in Figure 2 of Selten
 (International Journal of Game Theory, 1975)
 
    $ gambit-gnm e02.nfg
-
    Compute Nash equilibria using a global Newton method
    Gametracer version 0.2, Copyright (C) 2002, Ben Blum and Christian Shelton
    Gambit version |release|, Copyright (C) 1994-2025, The Gambit Project

doc/tools.ipa.rst

@@ -53,7 +53,6 @@ the reduced strategic form of the example in Figure 2 of Selten
 (International Journal of Game Theory, 1975)
 
    $ gambit-ipa e02.nfg
-
    Compute Nash equilibria using iterated polymatrix approximation
    Gametracer version 0.2, Copyright (C) 2002, Ben Blum and Christian Shelton
    Gambit version |release|, Copyright (C) 1994-2025, The Gambit Project

doc/tools.lcp.rst

@@ -9,7 +9,7 @@ computes Nash equilibria by finding solutions to a linear
 complementarity problem. For extensive games, the program uses the
 sequence form representation of the extensive game, as defined by
 Koller, Megiddo, and von Stengel [KolMegSte94]_, and applies the
-algorithm developed by Lemke. For strategic games, the program using
+algorithm developed by Lemke. For strategic games, the program uses
 the method of Lemke and Howson [LemHow64]_.  There exist strategic
 games for which some equilibria cannot be located by this method; see
 Shapley [Sha74]_.

src/pygambit/game.pxi

@@ -1497,7 +1497,7 @@ class Game:
             except KeyError:
                 raise KeyError(f"{funcname}(): no information set with label '{infoset}'")
         raise TypeError(
-            f"{funcname}(): {argname} must be Infoset or str, not {node.__class__.__name__}"
+            f"{funcname}(): {argname} must be Infoset or str, not {infoset.__class__.__name__}"
         )
 
     def _resolve_action(self,