Compile info and target to TDMProgram.compile (#659)

* add compile info and target

* update changelog

* Update .github/CHANGELOG.md

Co-authored-by: Mikhail Andrenkov <Mandrenkov@users.noreply.github.com>

* update docstring

* update docstring again

Co-authored-by: Mikhail Andrenkov <Mandrenkov@users.noreply.github.com>

.github/CHANGELOG.md

@@ -6,12 +6,18 @@
 
 <h3>Bug fixes</h3>
 
+* The `TDMProgram.compile_info` and `TDMProgram.target` fields are now set when
+  a `TDMProgram` is compiled using the "TDM" compiler.
+  [(#659)](https://github.com/XanaduAI/strawberryfields/pull/659)
+
 <h3>Documentation</h3>
 
 <h3>Contributors</h3>
 
 This release contains contributions from (in alphabetical order):
 
+Theodor Isacsson
+
 # Release 0.20.0 (current release)
 
 <h3>New features since last release</h3>

strawberryfields/program.py

@@ -598,7 +598,7 @@ def compile(self, *, device=None, compiler=None, **kwargs):
                 program compilation
             compiler (str, ~strawberryfields.compilers.Compiler): Compiler name or compile strategy
                 to use. If a device is specified, this overrides the compile strategy specified by
-                the hardware :class:`~.DevicSpec`.
+                the hardware :class:`~.DeviceSpec`.
 
         Keyword Args:
             optimize (bool): If True, try to optimize the program by merging and canceling gates.

strawberryfields/tdm/tdmprogram.py

@@ -437,9 +437,11 @@ def context(self, *args, shift="default"):
 
     # pylint: disable=too-many-branches
     def compile(self, *, device=None, compiler=None):
-        """Compile the time-domain program given a Strawberry Fields photonic hardware device specification.
+        """Compile the time-domain program given a Strawberry Fields photonic hardware device
+        specification.
 
-        Currently, the compilation is simply a check that the program matches the device.
+        The compilation checks that the program matches the device and sets the compile information
+        and the program target to the correct device target.
 
         Args:
             device (~strawberryfields.DeviceSpec): device specification object to use for
@@ -557,6 +559,8 @@ def compile(self, *, device=None, compiler=None):
                                     device.target, program_param, param_range
                                 )
                             )
+            self._compile_info = (device, "TDM")
+            self._target = device.target
             return self
 
         raise CircuitError("TDM programs cannot be compiled without a valid device specification.")