Port vr(1) to POSIX sh

4 files changed, 51 insertions, 64 deletions

diff --git a/ISSUES.markdown b/ISSUES.markdown
index bbaf12ae..c9a832d1 100644
--- a/ISSUES.markdown
+++ b/ISSUES.markdown
@@ -1,9 +1,6 @@
 Known issues
 ============
 
-*   vr() does not handle the newer version of Subversion repositories which
-    only have a .svn directory at the root level.
-*   It should also be POSIX portable without too much effort
 *   The terminfo files probably still do not work on NetBSD (needs retesting
     and manual page reading).
 *   man(1) completion doesn't work on OpenBSD as manpath(1) isn't a thing on
diff --git a/README.markdown b/README.markdown
index 558c8739..c79ffd1b 100644
--- a/README.markdown
+++ b/README.markdown
@@ -201,6 +201,8 @@ in `sh/shrc.d` to be loaded by any POSIX interactive shell. Those include:
 *   `ud()` changes into an indexed ancestor of a directory.
 *   `vim()` defines three functions to always use `vim(1)` as my `ex(1)`,
     `vi(1)` and `view(1)` implementation if it's available.
+*   `vr()` tries to change to the root directory of a source control
+    repository.
 
 There are a few other little tricks defined for other shells, mostly in
 `bash/bashrc.d`:
@@ -215,8 +217,6 @@ There are a few other little tricks defined for other shells, mostly in
 *   `readz()` is an alias for `read -d '' -r`.
 *   `vared()` allows interactively editing a variable with Readline, emulating
     a Zsh function I like by the same name.
-*   `vr()` tries to change to the root directory of a source control
-    repository.
 
 #### Completion
 
diff --git a/bash/bashrc.d/vr.bash b/bash/bashrc.d/vr.bash
deleted file mode 100644
index adabb395..00000000
--- a/bash/bashrc.d/vr.bash
+++ /dev/null
@@ -1,59 +0,0 @@
-# Move to the root directory of a VCS working copy
-vr() {
-    local path
-    path=${1:-"$PWD"}
-    path=${path%/}
-
-    # Raise some helpful errors
-    if [[ ! -e $path ]] ; then
-        printf 'bash: %s: %s: No such file or directory\n' \
-            "$FUNCNAME" "$path"
-        return 1
-    fi
-    if [[ ! -d $path ]] ; then
-        printf 'bash: %s: %s: Not a directory\n' \
-            "$FUNCNAME" "$path"
-        return 1
-    fi
-    if [[ ! -x $path ]] ; then
-        printf 'bash: %s: %s: Permission denied\n' \
-            "$FUNCNAME" "$path"
-        return 1
-    fi
-
-    # Ask Git the top level
-    local git_root
-    git_root=$(cd -- "$path" && git rev-parse --show-toplevel 2>/dev/null)
-    if [[ -n $git_root ]] ; then
-        cd -- "$git_root"
-        return
-    fi
-
-    # Ask Mercurial the top level
-    local hg_root
-    hg_root=$(cd -- "$path" && hg root 2>/dev/null)
-    if [[ -n $hg_root ]] ; then
-        cd -- "$hg_root"
-        return
-    fi
-
-    # If we have a .svn directory, iterate upwards until we find an ancestor
-    # that doesn't; hopefully that's the root
-    if [[ -d $path/.svn ]] ; then
-        local search
-        search=$path
-        while [[ -n $search ]] ; do
-            if [[ -d ${search%/*}/.svn ]] ; then
-                search=${search%/*}
-            else
-                cd -- "$search"
-                return
-            fi
-        done
-    fi
-
-    # Couldn't find repository root, say so
-    printf 'bash: %s: Failed to find repository root\n' \
-        "$FUNCNAME" >&2
-    return 1
-}
diff --git a/sh/shrc.d/vr.sh b/sh/shrc.d/vr.sh
new file mode 100644
index 00000000..b8a31aee
--- /dev/null
+++ b/sh/shrc.d/vr.sh
@@ -0,0 +1,49 @@
+# Move to the root directory of a VCS working copy
+vr() {
+
+    # Set positional parameters to the result of trying to figure out the
+    # repository root
+    set -- "$(
+
+        # Check we have at most one argument
+        if [ "$#" -gt 1 ] ; then
+            printf >&2 'vr(): Too many arguments\n'
+            exit 2
+        fi
+
+        # Get path from first argument, strip trailing slash
+        path=${1:-"$PWD"}
+        [ "$path" = / ] || path=${path%/}
+
+        # Step into the directory
+        cd -- "$path" || exit
+
+        # Ask Git the top level (good)
+        git rev-parse --show-toplevel 2>/dev/null && exit
+
+        # Ask Mercurial the top level (great)
+        hg root 2>/dev/null && exit
+
+        # If we can get SVN info, iterate upwards until we can't; hopefully
+        # that's the root (bad)
+        while svn info >/dev/null 2>&1 ; do
+            root=$PWD
+            [ "$root" = / ] && break
+            cd .. || exit
+        done
+        if [ -n "$root" ] ; then
+            printf '%s\n' "$root"
+            exit
+        fi
+
+        # Couldn't find repository root, say so
+        printf >&2 'vr(): Failed to find repository root\n'
+        exit 1
+    )"
+
+    # Check we figured out a target, or bail
+    [ -n "$1" ] || return
+
+    # Try to change into the determined directory
+    command cd -- "$@"
+}