Add issue template for regression (#713)

Author: mauvilsa

.github/ISSUE_TEMPLATE/1-bug.md

@@ -1,6 +1,6 @@
 ---
 name: Bug report
-about: Create a report to help us improve
+about: Report for something that doesn't work as expected
 title: ''
 labels: bug
 assignees: ''
@@ -16,19 +16,24 @@ assignees: ''
 
 <!--
 Please include a code snippet that reproduces the bug and the output that
-running it gives. The following snippet templates might help:
+running it gives. The following snippet templates might help. Replace "..." with
+actual implementation details.
 
-1. Using the CLI function
+1. Using the auto_cli function
 
 ```python
-from jsonargparse import CLI
+from jsonargparse import auto_cli
 
 # Here define one or more functions or classes
 def func1(param1: int, ...):
     ...
 
-# Run the CLI providing the components
-CLI([func1, ...], exit_on_error=False)
+# Run the CLI providing the components and arguments
+auto_cli(
+    [func1, ...],
+    args=["--param1=value1", ...],
+    exit_on_error=False,
+)
 ```
 
 2. Manually constructing a parser
@@ -39,11 +44,11 @@ from jsonargparse import ArgumentParser
 parser = ArgumentParser(exit_on_error=False)
 # Here add to the parser only argument(s) relevant to the problem
 
-# If a yaml config is required, it can be included in the same snippet as follows:
-import yaml
+# If a config is required, it can be included in the same snippet as follows:
+import json
 
 parser.add_argument("--config", action="config")
-config = yaml.safe_dump(
+config = json.dumps(
     {
         "key1": "val1",
     }

.github/ISSUE_TEMPLATE/2-regression.md

@@ -0,0 +1,94 @@
+---
+name: Regression report
+about: Report for something that used to work but doesn't anymore
+title: ''
+labels: bug
+assignees: ''
+---
+
+<!-- If you like this project, please ⭐ star it https://github.com/omni-us/jsonargparse/ -->
+
+## 🕰️ Regression report
+
+<!-- A clear and concise description of the regression. -->
+
+### To reproduce
+
+<!--
+Please include a code snippet that reproduces the regression. Make sure that it
+is a script that can be used to run git bisect. This means that when code works
+correctly, the script terminates with zero exit code. When it fails an exception
+is raised. The following snippet templates might help. Replace "..." with actual
+implementation details.
+
+1. a) Using the auto_cli function
+
+```python
+#!/usr/bin/env python3
+
+from jsonargparse import auto_cli
+
+# Here define one or more functions or classes
+def func1(param1: int, ...):
+    ...
+
+# Run the CLI providing the components and arguments
+auto_cli(
+    [func1, ...],
+    args=["--param1=value1", ...],
+    exit_on_error=False,
+)
+```
+
+1. b) Manually constructing a parser
+
+```python
+#!/usr/bin/env python3
+
+from jsonargparse import ArgumentParser
+
+parser = ArgumentParser(exit_on_error=False)
+# Here add to the parser only argument(s) relevant to the problem
+
+# If a config is required, it can be included in the same snippet as follows:
+import json
+
+parser.add_argument("--config", action="config")
+config = json.dumps(
+    {
+        "key1": "val1",
+    }
+)
+
+# If the problem is when parsing arguments
+result = parser.parse_args([f"--config={config}", "--key2=val2", ...])
+
+# If the problem is in class instantiation
+parser.instantiate_classes(result)
+```
+
+2. Preferably, run git bisect and include in the report the git commit hash that
+caused the regression. This would be like:
+
+```
+chmod +x regression.py  # make script executable
+pip3 install -e .  # install as editable
+git bisect start
+git bisect bad <version-tag-latest>
+git bisect good <version-tag-known-good>
+git bisect run ./regression.py
+```
+-->
+
+### Prior behavior
+
+<!-- Please describe the prior behavior in detail, and contrast it with the behavior you are currently observing. -->
+
+### Environment
+
+<!-- Fill in the list below. -->
+
+- jsonargparse version:
+- Python version:
+- How jsonargparse was installed:
+- OS: