miscellaneous bug fixes (#13291)

* fix for emscripten etc

* add testcase for #13290

* replace deprecated isNilOrWhitespace

lib/pure/includes/osenv.nim

@@ -68,7 +68,7 @@ when defined(windows) and not defined(nimscript):
 
 else:
   const
-    useNSGetEnviron = (defined(macosx) and not defined(ios)) or defined(nimscript)
+    useNSGetEnviron = (defined(macosx) and not defined(ios) and not defined(emscripten)) or defined(nimscript)
 
   when useNSGetEnviron:
     # From the manual:

lib/system/timers.nim

@@ -31,7 +31,7 @@ when defined(windows):
 
     result = Nanos(float64(a.int64 - b.int64) * performanceCounterRate)
 
-elif defined(macosx):
+elif defined(macosx) and not defined(emscripten):
   type
     MachTimebaseInfoData {.pure, final,
         importc: "mach_timebase_info_data_t",

testament/htmlgen.nim

@@ -52,7 +52,7 @@ proc generateTestResultPanelPartial(outfile: File, testResultRow: JsonNode) =
     trId, name, target, category, action, resultDescription,
     timestamp, result, resultSign, panelCtxClass, textCtxClass, bgCtxClass
   )
-  if expected.isNilOrWhitespace() and gotten.isNilOrWhitespace():
+  if expected.isEmptyOrWhitespace() and gotten.isEmptyOrWhitespace():
     outfile.generateHtmlTestresultOutputNone()
   else:
     outfile.generateHtmlTestresultOutputDetails(

tests/system/tsystem_misc.nim

@@ -184,3 +184,12 @@ proc testMinMax(a,b: float32) =
 
 testMinMax(0.0, NaN)
 testMinMax(NaN, 0.0)
+
+
+block:
+  type Foo = enum
+    k1, k2
+  var
+    a = {k1}
+    b = {k1,k2}
+  doAssert a < b