Testcases review:

- comment on why the case exists,

- add an M2 at the end to later allow automatic simulation stop,

- move comments to the end to avoid filling the serial buffer with
  stuff unrelated to movements,

- make sure there's a line ending at the end of the file and

- use Windows line endings (they're more difficult to handle).

testcases/excessive-digits.gcode

@@ -269,5 +269,6 @@ G01 X4.6318097368 Y-17.4465880476 Z0.0845552982 F2704.9457125719
 G01 X-5.5661914530 Y-9.8067193712 Z-0.1384208129 F2803.7432582416
 G01 X-15.7641926427 Y-2.1668506949 Z-0.3613969240 F2803.7432582416
 G01 X-25.9621938325 Y5.4730179814 Z-0.5843730351 F2803.7432582416
-
-
+M2
+(This example has shown to do nonsense.)
+(The same with 3 digits to the right of the decimal always worked.)

testcases/nullmoves.gcode

@@ -1,5 +1,3 @@
-(run this with STEPS_PER_M_X < 500000)
-(for example, the typical 80000)
 G21
 G90
 G1 X5 F400
@@ -14,3 +12,5 @@ G1 X20.003
 G1 X25
 G1 X0
 M2
+(run this with STEPS_PER_M_X < 500000)
+(for example, the typical 80000)

testcases/smooth-curves.gcode

@@ -1,5 +1,3 @@
-(This is test code for)
-(the look-ahead algorithm)
 G21
 G90
 G0 X69.0909 Y11.6477 Z1.0
@@ -169,4 +167,5 @@ G0 Z1.0
 G4
 M106 S0
 M2
-
+(This is test code for)
+(the look-ahead algorithm)

testcases/straight-speeds.gcode

@@ -1,5 +1,3 @@
-(This is test code for)
-(the look-ahead algorithm)
 G21
 G90
 G1 X5 F400
@@ -14,3 +12,5 @@ G1 X20 Y20 F400
 G1 X100 Y100 F1500
 G1 X0 Y0
 M2
+(This is test code for)
+(the look-ahead algorithm)

testcases/triangle-odd.gcode

@@ -1,7 +1,7 @@
-(This demonstrates an odd speed)
 G21
 G90
 G1 X5 F300
 G1 Y9
 G1 X0 Y0
 M2
+(This demonstrates an odd speed)

testcases/triangle.gcode

@@ -1,4 +1,3 @@
-(This is a test case for plotting scripts)
 G21
 G90
 G1 X5 F800
@@ -7,3 +6,4 @@ G1 X20
 G1 X40 Y20
 G1 X0 Y0
 M2
+(This is a test case for plotting scripts)