fix nim-lang#1994 gorge, staticExec now error at CT on exitCode !=0

changelog.md

@@ -67,7 +67,10 @@
 - two poorly documented and not used modules (`subexes`, `scgi`) were moved to
   graveyard (they are available as Nimble packages)
 
-
+- `gorge`, `staticExec` now give compile time error if exitCode is not 0 instead of
+  silently ignoring errors. See https://github.com/nim-lang/Nim/issues/1994#issuecomment-327904129
+  Use `--experimental:gorgeIgnoreExitCodeDeprecated` to get old behavior, or use
+  `gorgeEx` to get `tuple[output: string, exitCode: int]`.
 
 #### Breaking changes in the compiler
 

compiler/options.nim

@@ -127,6 +127,8 @@ type
     forLoopMacros,
     caseStmtMacros,
     codeReordering,
+    # deprecated behavior `foo` is named: `fooDeprecated`
+    gorgeIgnoreExitCodeDeprecated,
 
   SymbolFilesOption* = enum
     disabledSf, writeOnlySf, readOnlySf, v2Sf

compiler/vm.nim

@@ -1429,9 +1429,15 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
         let rd = c.code[pc].regA
 
         createStr regs[ra]
-        regs[ra].node.strVal = opGorge(regs[rb].node.strVal,
-                                      regs[rc].node.strVal, regs[rd].node.strVal,
-                                      c.debug[pc], c.config)[0]
+        let cmd = regs[rb].node.strVal
+        let input = regs[rc].node.strVal
+        let ret = opGorge(cmd, input, regs[rd].node.strVal, c.debug[pc], c.config)
+        # note: can't be enabled locally via {.experimental: gorgeIgnoreExitCodeDeprecated.},
+        # as to be a global flag, unless VM starts supporting this (eg with `c.features`)
+        if gorgeIgnoreExitCodeDeprecated notin c.config.features:
+          if ret[1] != 0:
+            stackTrace(c, tos, pc, "gorge failed: " & $(exitCode: ret[1], cmd: cmd, input: input))
+        regs[ra].node.strVal = ret[0]
       else:
         globalError(c.config, c.debug[pc], "VM is not built with 'gorge' support")
     of opcNError, opcNWarning, opcNHint:

tests/vm/tvmops.nim

@@ -5,6 +5,8 @@ import os
 import math
 import strutils
 
+const nonexistant = "D20190116T211842"
+
 template forceConst(a: untyped): untyped =
   ## Force evaluation at CT, useful for example here:
   ## `callFoo(forceConst(getBar1()), getBar2())`
@@ -22,7 +24,7 @@ static:
     let ret = gorgeEx(nim & " --version")
     doAssert ret.exitCode == 0
     doAssert ret.output.contains "Nim Compiler"
-    let ret2 = gorgeEx(nim & " --unexistant")
+    let ret2 = gorgeEx(nim & " --" & nonexistant)
     doAssert ret2.exitCode != 0
     let output3 = gorge(nim & " --version")
     doAssert output3.contains "Nim Compiler"
@@ -44,4 +46,5 @@ block:
   # Check against bugs like #9176
   doAssert getCurrentCompilerExe() == forceConst(getCurrentCompilerExe())
   if false: #pending #9176
-    doAssert gorgeEx("unexistant") == forceConst(gorgeEx("unexistant"))
+    doAssert gorgeEx(nonexistant) == forceConst(gorgeEx(nonexistant))
+

tests/vm/tvmops_fail.nim

@@ -0,0 +1,15 @@
+discard """
+  errormsg: '''gorge failed: (exitCode: 127, cmd: "D20190116T211842", input: "")'''
+"""
+
+# issue #1994
+
+#[
+This doesn't work as VM error isn't catchable
+block:
+  static:
+    doAssertRaises(AssertionError):
+]#
+
+const nonexistant = "D20190116T211842"
+const a = gorge(nonexistant)