extruder: Deprecate old extruder commands and shared_heater config option

Deprecate SET_EXTRUDER_STEP_DISTANCE and SYNC_STEPPER_TO_EXTRUDER.
Recommend using SET_EXTRUDER_ROTATION_DISTANCE and
SYNC_EXTRUDER_MOTION.

Deprecate the extruder "shared_heater" option and reocmmend using
extruder_stepper config sections to obtain the same functionality.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

4 files changed, 16 insertions, 20 deletions

diff --git a/docs/Config_Changes.md b/docs/Config_Changes.md
index ead2445c..45d19acb 100644
--- a/docs/Config_Changes.md
+++ b/docs/Config_Changes.md
@@ -8,6 +8,18 @@ All dates in this document are approximate.
 
 ## Changes
 
+20220210: The `SYNC_STEPPER_TO_EXTRUDER` command is deprecated; the
+`SET_EXTRUDER_STEP_DISTANCE` command is deprecated; the
+[extruder](Config_Reference.md#extruder) `shared_heater` config option
+is deprecated. These features will be removed in the near future.
+Replace `SET_EXTRUDER_STEP_DISTANCE` with
+`SET_EXTRUDER_ROTATION_DISTANCE`. Replace `SYNC_STEPPER_TO_EXTRUDER`
+with `SYNC_EXTRUDER_MOTION`. Replace extruder config sections using
+`shared_heater` with
+[extruder_stepper](Config_Reference.md#extruder_stepper) config
+sections and update any activation macros to use
+[SYNC_EXTRUDER_MOTION](G-Codes.md#sync_extruder_motion).
+
 20220116: The tmc2130, tmc2208, tmc2209, and tmc2660 `run_current`
 calculation code has changed. For some `run_current` settings the
 drivers may now be configured differently. This new configuration
diff --git a/docs/Config_Reference.md b/docs/Config_Reference.md
index f4b36e70..223b576f 100644
--- a/docs/Config_Reference.md
+++ b/docs/Config_Reference.md
@@ -1781,12 +1781,7 @@ for an example configuration.
 #   See the "extruder" section for available stepper and heater
 #   parameters.
 #shared_heater:
-#   If this extruder uses the same heater already defined for another
-#   extruder then place the name of that extruder here. For example,
-#   should extruder3 and extruder4 share a heater then the extruder3
-#   config section should define the heater and the extruder4 section
-#   should specify "shared_heater: extruder3". The default is to not
-#   reuse an existing heater.
+#   This option is deprecated and should no longer be specified.
 ```
 
 ### [dual_carriage]
diff --git a/docs/G-Codes.md b/docs/G-Codes.md
index 2ff7b7bf..1591c88d 100644
--- a/docs/G-Codes.md
+++ b/docs/G-Codes.md
@@ -322,22 +322,10 @@ config section). If MOTION_QUEUE is an empty string then the stepper
 will be desynchronized from all extruder movement.
 
 #### SET_EXTRUDER_STEP_DISTANCE
-`SET_EXTRUDER_STEP_DISTANCE EXTRUDER=<config_name>
-[DISTANCE=<distance>]`: Set a new value for the provided extruder's
-"step distance". The "step distance" is
-`rotation_distance/(full_steps_per_rotation*microsteps)`. Value is not
-retained on Klipper reset. Use with caution as small changes can
-result in excessive pressure between extruder and hot end. Do proper
-calibration with filament before use. If 'DISTANCE' value is not
-included command will return current step distance.
+This command is deprecated and will be removed in the near future.
 
 #### SYNC_STEPPER_TO_EXTRUDER
-`SYNC_STEPPER_TO_EXTRUDER STEPPER=<name> EXTRUDER=<name>`: This
-command will cause the given extruder STEPPER (as specified in an
-[extruder](Config_Reference#extruder) or
-[extruder stepper](Config_Reference#extruder_stepper) config section)
-to become synchronized to the given EXTRUDER. If EXTRUDER is an empty
-string then the stepper will not be synchronized to an extruder.
+This command is deprecated and will be removed in the near future.
 
 ### [fan_generic]
 
diff --git a/klippy/kinematics/extruder.py b/klippy/kinematics/extruder.py
index 9b98eaf8..99d5daf8 100644
--- a/klippy/kinematics/extruder.py
+++ b/klippy/kinematics/extruder.py
@@ -150,6 +150,7 @@ class PrinterExtruder:
         if shared_heater is None:
             self.heater = pheaters.setup_heater(config, gcode_id)
         else:
+            config.deprecate('shared_heater')
             self.heater = pheaters.lookup_heater(shared_heater)
         # Setup kinematic checks
         self.nozzle_diameter = config.getfloat('nozzle_diameter', above=0.)