Allow removal of reverse dependencies with uninstall --deps flag (#601)

* Fix for #398

* Updated fix for #398

* Enable uninstall of reverse deps

* Update README

* Updates based on feedback

readme.markdown

@@ -221,8 +221,8 @@ instead of a name.
 ### nimble uninstall
 
 The ``uninstall`` command will remove an installed package. Attempting to remove
-a package which other packages depend on is disallowed and will result in an
-error. You must currently manually remove the reverse dependencies first.
+a package which other packages depend on will result in an error. You can use the
+``--inclDeps`` or ``-i`` flag to remove all dependent packages along with the package.
 
 Similar to the ``install`` command you can specify a version range, for example:
 
@@ -749,16 +749,16 @@ to ensure that the dependencies you specified are correct.
 ### Compile with `nim` after changing the nimble directory
 
 The Nim compiler has been preconfigured to look at the default nimble directory while compiling,
-so no extra step is required to use nimble managed packages in your code. 
-However, if you are using a custom `nimbleDir`, you need to specify the 
+so no extra step is required to use nimble managed packages in your code.
+However, if you are using a custom `nimbleDir`, you need to specify the
 `--nimblePath:PATH` option. For example,
 if your `nimble` directory is located at `/some/custom/path/nimble`, this should work:
 
 ```
 nim c --nimblePath:/some/custom/path/nimble/pkgs main.nim
-``` 
+```
 
-Some code editors rely on `nim check` to check for errors under the hood (e.g. VScode), 
+Some code editors rely on `nim check` to check for errors under the hood (e.g. VScode),
 and the editor extension may not allow users to pass custom option to `nim check`, which
 will cause `nim check` to scream `Error: cannot open file:<the_package>`. In this case,
 you will have to use [Nim compiler's configuration files](https://nim-lang.org/docs/nimc.html#compiler-usage-configuration-files). Simply add the line:

src/nimble.nim

@@ -846,22 +846,25 @@ proc uninstall(options: Options) =
     for pkg in pkgList:
       # Check whether any packages depend on the ones the user is trying to
       # uninstall.
-      let revDeps = getRevDeps(options, pkg)
-      var reason = ""
-      if revDeps.len == 1:
-        reason = "$1 ($2) depends on it" % [revDeps[0].name, $revDeps[0].ver]
+      if options.uninstallRevDeps:
+        getAllRevDeps(options, pkg, pkgsToDelete)
       else:
-        for i in 0 ..< revDeps.len:
-          reason.add("$1 ($2)" % [revDeps[i].name, $revDeps[i].ver])
-          if i != revDeps.len-1:
-            reason.add ", "
-        reason.add " depend on it"
+        let revDeps = getRevDeps(options, pkg)
+        var reason = ""
+        if revDeps.len == 1:
+          reason = "$1 ($2) depends on it" % [revDeps[0].name, $revDeps[0].ver]
+        else:
+          for i in 0 ..< revDeps.len:
+            reason.add("$1 ($2)" % [revDeps[i].name, $revDeps[i].ver])
+            if i != revDeps.len-1:
+              reason.add ", "
+          reason.add " depend on it"
 
-      if revDeps.len > 0:
-        errors.add("Cannot uninstall $1 ($2) because $3" %
-                   [pkgTup.name, pkg.specialVersion, reason])
-      else:
-        pkgsToDelete.add pkg
+        if revDeps.len > 0:
+          errors.add("Cannot uninstall $1 ($2) because $3" %
+                     [pkgTup.name, pkg.specialVersion, reason])
+        else:
+          pkgsToDelete.add pkg
 
     if pkgsToDelete.len == 0:
       raise newException(NimbleError, "\n  " & errors.join("\n  "))
@@ -1007,7 +1010,7 @@ proc test(options: Options) =
         existsBefore = existsFile(binFileName)
 
       execBackend(optsCopy)
-      
+
       let
         existsAfter = existsFile(binFileName)
         canRemove = not existsBefore and existsAfter

src/nimblepkg/options.nim

@@ -10,6 +10,7 @@ type
   Options* = object
     forcePrompts*: ForcePrompt
     depsOnly*: bool
+    uninstallRevDeps*: bool
     queryVersions*: bool
     queryInstalled*: bool
     nimbleDir*: string
@@ -71,6 +72,7 @@ Commands:
                                   The current working directory needs to be the
                                   toplevel directory of the Nimble package.
   uninstall    [pkgname, ...]     Uninstalls a list of packages.
+               [-i, --inclDeps]   Uninstall package and dependent package(s).
   build                           Builds a package.
   c, cc, js    [opts, ...] f.nim  Builds a file inside a package. Passes options
                                   to the Nim compiler.
@@ -301,6 +303,12 @@ proc parseFlag*(flag, val: string, result: var Options, kind = cmdLongOption) =
         result.depsOnly = true
       else:
         wasFlagHandled = false
+    of actionUninstall:
+      case f
+      of "incldeps", "i":
+        result.uninstallRevDeps = true
+      else:
+        wasFlagHandled = false
     of actionCompile, actionDoc, actionBuild:
       let prefix = if kind == cmdShortOption: "-" else: "--"
       if val == "":

src/nimblepkg/packageinfo.nim

@@ -538,6 +538,10 @@ proc getPkgDest*(pkgInfo: PackageInfo, options: Options): string =
   let pkgDestDir = options.getPkgsDir() / (pkgInfo.name & versionStr)
   return pkgDestDir
 
+proc `==`*(pkg1: PackageInfo, pkg2: PackageInfo): bool =
+  if pkg1.name == pkg2.name and pkg1.myPath == pkg2.myPath:
+    return true
+
 when isMainModule:
   doAssert getNameVersion("/home/user/.nimble/libs/packagea-0.1") ==
       ("packagea", "0.1")

src/nimblepkg/reversedeps.nim

@@ -76,6 +76,19 @@ proc getRevDeps*(options: Options, pkg: PackageInfo): seq[PkgTuple] =
 
       result.add(pkgTup)
 
+proc getAllRevDeps*(options: Options, pkg: PackageInfo, result: var seq[PackageInfo]) =
+  if pkg in result:
+    return
+
+  let installedPkgs = getInstalledPkgsMin(options.getPkgsDir(), options)
+  for rdepTup in getRevDeps(options, pkg):
+    for rdepInfo in findAllPkgs(installedPkgs, rdepTup):
+      if rdepInfo in result:
+        continue
+
+      getAllRevDeps(options, rdepInfo, result)
+  result.add pkg
+
 when isMainModule:
   var nimbleData = %{"reverseDeps": newJObject()}
 

tests/tester.nim

@@ -568,6 +568,27 @@ suite "reverse dependencies":
     verify execNimbleYes("remove", "pkgA")
     verify execNimbleYes("remove", "mydep")
 
+  test "revdep fail test":
+    cd "revdep/mydep":
+      verify execNimbleYes("install")
+
+    cd "revdep/pkgWithDep":
+      verify execNimbleYes("install")
+
+    let (output, exitCode) = execNimble("uninstall", "mydep")
+    checkpoint output
+    check output.processOutput.inLines("cannot uninstall mydep")
+    check exitCode == QuitFailure
+
+  test "revdep -i test":
+    cd "revdep/mydep":
+      verify execNimbleYes("install")
+
+    cd "revdep/pkgWithDep":
+      verify execNimbleYes("install")
+
+    verify execNimbleYes("remove", "mydep", "-i")
+
   test "issue #373":
     cd "revdep/mydep":
       verify execNimbleYes("install")