[MSHARED-969] Environment variable with null value

[jira-importer]

Slawomir Jaranowski opened MSHARED-969 and commented

When we add environment variable with null value then to executed process is pass variable with "null" as string.

Variable with null value should not be set, when executed process will try to get this variable will receive null as we expect.

---

Affects: maven-shared-utils-3.3.3

Issue Links:

• MINVOKER-273 Environment variable with empty value
  ("causes")
• MSHARED-971 System environment variable are always added to maven-invoker

Remote Links:

• GitHub Pull Request #68
  

[jira-importer]

Markus Karg commented

At least on Windows it is impossible to store null in env vars. According to Windows API description doing so will remove the variable from the environment. Can other OS experts confirm that this is the same on Linux, MacOS, etc? If so, I would be +1 for fixing this issue.

[jira-importer]

Slawomir Jaranowski commented

In fixed code system environment is not set yet - it happens later.

maven-shared-utils/src/main/java/org/apache/maven/shared/utils/cli/Commandline.java

Lines 408 to 425 in 360fd97

	if ( workingDir == null )
	{
	process = Runtime.getRuntime().exec( getShellCommandline(), environment );
	}
	else
	{
	if ( !workingDir.exists() )
	{
	throw new CommandLineException(
	"Working directory \"" + workingDir.getPath() + "\" does not exist!" );
	}
	else if ( !workingDir.isDirectory() )
	{
	throw new CommandLineException(
	"Path \"" + workingDir.getPath() + "\" does not specify a directory." );
	}
	process = Runtime.getRuntime().exec( getShellCommandline(), environment, workingDir );

by call:
{{}}

String[] environment = getEnvironmentVariables();
...
process = Runtime.getRuntime().exec( getShellCommandline(), environment ); 

}}I fixed method {{getEnvironmentVariables()

In original code we never have null as environment value

environmentVars[i] = name + "=" + value;

if value was null - it was replaced by "null" string.

[jira-importer]

Slawomir Jaranowski commented

After my fix we have another feature, we can remove some variable from system environment.

In method getEnvironmentVariables first is called addSystemEnvironment which copied current system variable to local list, and when variable with the same name exist it is not copied from system.

Next in getEnvironmentVariables we filter variables wich have null value and in consequence we can filter system variables.

I added unit test to confirm this behavior.

 

[jira-importer]

Slawomir Jaranowski commented

and some other discovery MSHARED-971