Portable Build Scripts

It is possible and sometimes expected to have a copy of Invoke-Build tools kept together with build scripts. This makes the build tool set portable, i.e. build scripts may be invoked on any machine without Invoke-Build installed.

Another reason to keep a copy of Invoke-Build with scripts is use of multiple build engine versions, potentially incompatible. Existing build scripts do not have to be upgraded for a newer version, they may continue using the old copy.

Build scripts are already portable if they do not call Invoke-Build.ps1 (nested build) and the satellite scripts Build-Parallel.ps1, Resolve-MSBuild.ps1, Show-TaskHelp.ps1.

Otherwise, build scripts should follow the rule: invoke the above scripts by their aliases defined by the engine: Invoke-Build, Build-Parallel, Resolve-MSBuild, Show-TaskHelp.

These aliases guarantee the correct scripts invoked, even if there are other scripts with same names in the system path. Namely,

• Invoke-Build is the alias of the currently running engine Invoke-Build.ps1;
• Build-Parallel is the alias of Build-Parallel.ps1 in the engine folder;
• etc.

Thus, nested calls of Invoke-Build from tasks invoke Invoke-Build.ps1 which is currently running (e.g. which is kept together with the scripts). Compare: calls to Invoke-Build.ps1, i.e. with the extension, may fail because either Invoke-Build.ps1 is not in the system path or its version is incompatible.

Only top level commands may invoke builds as Invoke-Build.ps1 (assuming it is in the path) or <some-path>/Invoke-Build.ps1 (assuming it is there).