@@ -1,14 +1,13 @@
-if not set --query SCRIPTURA_ROOT
-    if set --query SD_ROOT
+function scriptura
+    argparse --stop-nonopt h/help n/new e/edit w/which c/cat -- $argv
+    or return
+
+    set --query SCRIPTURA_ROOT
+    or if set --query SD_ROOT
         set --function SCRIPTURA_ROOT $SD_ROOT
     else
         set --function SCRIPTURA_ROOT "$HOME/sd"
     end
-end
-
-function scriptura
-    argparse --stop-nonopt h/help n/new e/edit w/which c/cat -- $argv
-    or return
 
     if not path is $SCRIPTURA_ROOT
         if set --query _flag_new
@@ -40,44 +39,48 @@ break
         end
     end
 
-    set argv $argv[(math $i + 1)..-1]
+    set --local begin (math $i + 1)
+    if test $begin -gt (count $argv)
+        set begin 1
+    end
+    set --local remaining $argv[$begin..-1]
 
     if set --query _flag_help
         __scriptura_help $target
-        return 0
+        return $status
     end
 
     if set --query _flag_new
         __scriptura_new $target
-        return 0
+        return $status
     end
 
     if set --query _flag_edit
         __scriptura_edit $target
-        return 0
+        return $status
     end
 
     if set --query _flag_which
-        __scriptura_which $target $argv
-        return 0
+        __scriptura_which $target $remaining
+        return $status
     end
 
     if set --query _flag_cat
         __scriptura_cat $target
-        return 0
+        return $status
     end
 
     if set --query script
         if path is --perm exec $target
-            $target $argv
+            $target $remaining
         else
             echo "scriptura: $target is not executable" >&2
             __scriptura_cat $target
         end
-    else if path is --type dir $target
+    else if path is --type dir $target; and not test "$target" = "$SCRIPTURA_ROOT"
         __scriptura_list $target
     else
-        echo "scriptura: don't know what to do with target \"$target\"" >&2
+        echo "scriptura: don't know what to do with target \"$remaining\"" >&2
     end
 end
 
@@ -116,7 +119,7 @@ end
 end
 
 function __scriptura_desc --argument-names file
-    string match --groups-only --regex '^#\s*([^!].*)$' <$file
+    string match --groups-only --regex '^#\s*([^!].*)$' <$file | string join "\n"
 end
 
 function __scriptura_file_help --argument-names file

@@ -0,0 +1,240 @@
+#!/usr/bin/env fish
+
+# Setup test environment
+set --global test_root (mktemp -d)
+set --global original_scriptura_root $SCRIPTURA_ROOT
+set --global original_sd_root $SD_ROOT
+
+# Helper function to clean up
+function cleanup
+    rm -rf $test_root
+    if set --query original_scriptura_root
+        set --global --export SCRIPTURA_ROOT $original_scriptura_root
+    else
+        set --erase --global SCRIPTURA_ROOT
+    end
+    if set --query original_sd_root
+        set --global --export SD_ROOT $original_sd_root
+    else
+        set --erase --global SD_ROOT
+    end
+end
+
+# Test: SCRIPTURA_ROOT defaults to ~/sd when not set
+@test "SCRIPTURA_ROOT defaults to ~/sd when not set" (
+    set --erase SCRIPTURA_ROOT
+    set --erase SD_ROOT
+    source $(status dirname)/../functions/scriptura.fish
+    scriptura
+) = "\$SCRIPTURA_ROOT $HOME/sd does not exist, use `scriptura --new` to create it"
+
+# Test: SCRIPTURA_ROOT uses SD_ROOT when set
+@test "SCRIPTURA_ROOT uses SD_ROOT when set" (
+    set --erase SCRIPTURA_ROOT
+    set --global --export SD_ROOT "/custom/sd"
+    source $(status dirname)/../functions/scriptura.fish
+    scriptura
+) = "\$SCRIPTURA_ROOT /custom/sd does not exist, use `scriptura --new` to create it"
+
+# Test: SCRIPTURA_ROOT uses existing value when set
+@test "SCRIPTURA_ROOT uses existing value when set" (
+    set --global --export SCRIPTURA_ROOT "/existing/root"
+    set --global --export SD_ROOT "/custom/sd"
+    source $(status dirname)/../functions/scriptura.fish
+    scriptura
+) = "\$SCRIPTURA_ROOT /existing/root does not exist, use `scriptura --new` to create it"
+
+# Test: usage is shown when no arguments provided
+@test "usage is shown when no arguments provided" -n (
+    set --global --export SCRIPTURA_ROOT $test_root
+    mkdir -p $test_root
+    scriptura 2>&1 | string match --regex "Usage:"
+)
+
+# Test: error when SCRIPTURA_ROOT doesn't exist and --new not used
+@test "error when SCRIPTURA_ROOT doesn't exist and --new not used" -n (
+    set --global --export SCRIPTURA_ROOT "/nonexistent/path"
+    scriptura 2>&1 | string match --regex "does not exist"
+)
+
+# Test: --new creates SCRIPTURA_ROOT if it doesn't exist
+@test "--new creates SCRIPTURA_ROOT if it doesn't exist" (
+    set --global --export SCRIPTURA_ROOT "$test_root/new_root"
+    scriptura --new > /dev/null 2>&1
+    path is --type dir $test_root/new_root
+) $status -eq 0
+
+# Test: --new creates a new script
+@test "--new creates a new script" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    set --global --export SCRIPTURA_EDITOR "touch"
+    scriptura --new test_script
+    path is --type file --perm exec "$test_root/test_script"
+) $status -eq 0
+
+# Test: --new creates script with shebang
+@test "--new creates script with shebang" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    set --global --export SCRIPTURA_EDITOR "touch"
+    scriptura --new shebang_test
+    head -n 1 "$test_root/shebang_test"
+) = "#!/usr/bin/env fish"
+
+# Test: --new fails if script already exists
+@test "--new fails if script already exists" -n (
+    set --global --export SCRIPTURA_ROOT $test_root
+    touch "$test_root/existing_script"
+    scriptura --new existing_script 2>&1 | string match --regex "already exists"
+)
+
+# Test: --which shows path for executable script
+@test "--which shows path for executable script" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\necho test\n" > "$test_root/which_test"
+    chmod +x "$test_root/which_test"
+    scriptura --which which_test
+) = "$test_root/which_test"
+
+# Test: --which fails for non-executable file
+@test "--which fails for non-executable file" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    touch "$test_root/non_exec"
+    scriptura --which non_exec
+) $status -ne 0
+
+# Test: --cat displays script content
+@test "--cat displays script content" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    echo "# Test content" > "$test_root/cat_test"
+    scriptura --cat cat_test
+) = "# Test content"
+
+# Test: --help shows help for script
+@test "--help shows help for script" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\n# This is a test script\necho hello\n" > "$test_root/help_test"
+    chmod +x "$test_root/help_test"
+    scriptura --help help_test
+) = "This is a test script"
+
+# Test: script execution works for executable scripts
+@test "script execution works for executable scripts" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\necho 'executed successfully'\n" > "$test_root/exec_test"
+    chmod +x "$test_root/exec_test"
+    scriptura exec_test
+) = "executed successfully"
+
+# Test: non-executable script shows error and content
+@test "non-executable script shows error and content" -n (
+    set --global --export SCRIPTURA_ROOT $test_root
+    echo "# Non-executable content" > "$test_root/non_exec_test"
+    scriptura non_exec_test 2>&1 | string match --regex "not executable"
+)
+
+# Test: directory listing shows directories
+@test "directory listing shows directories" -n (
+    set --global --export SCRIPTURA_ROOT $test_root
+    mkdir -p "$test_root/test_dir"
+    scriptura 2>&1 | string match --regex "test_dir"
+)
+
+# Test: directory listing shows executable files
+@test "directory listing shows executable files" -n (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\n# Test script\n" > "$test_root/list_test"
+    chmod +x "$test_root/list_test"
+    scriptura 2>&1 | string match --regex "list_test"
+)
+
+# Test: help file is used for directories
+@test "help file is used for directories" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    mkdir -p "$test_root/help_dir"
+    echo "Directory help text" > "$test_root/help_dir/help"
+    scriptura --help help_dir
+) = "Directory help text"
+
+# Test: .help file is used for scripts
+@test ".help file is used for scripts" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\n" > "$test_root/help_file_test"
+    chmod +x "$test_root/help_file_test"
+    echo "External help text" > "$test_root/help_file_test.help"
+    scriptura --help help_file_test
+) = "External help text"
+
+# Test: script description extracted from comments
+@test "script description extracted from comments" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\n# This is the description\n# Another comment\n" > "$test_root/desc_test"
+    chmod +x "$test_root/desc_test"
+    scriptura --help desc_test
+) = "This is the description\nAnother comment"
+
+# Test: nested path resolution works
+@test "nested path resolution works" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    mkdir -p "$test_root/level1/level2"
+    printf "#!/usr/bin/env fish\necho nested\n" > "$test_root/level1/level2/nested_test"
+    chmod +x "$test_root/level1/level2/nested_test"
+    scriptura level1 level2 nested_test
+) = nested
+
+# Test: arguments passed to executed script
+@test "arguments passed to executed script" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\necho \$argv\n" > "$test_root/args_test"
+    chmod +x "$test_root/args_test"
+    scriptura args_test arg1 arg2
+) = "arg1 arg2"
+
+# Test: -- stops argument processing
+@test "-- stops argument processing" -n (
+    set --global --export SCRIPTURA_ROOT $test_root
+    mkdir -p "$test_root/dash_test"
+    printf "#!/usr/bin/env fish\necho dash_dir\n" > "$test_root/dash_test/script"
+    chmod +x "$test_root/dash_test/script"
+    scriptura dash_test -- script 2>&1 | string match --regex "^script\s+ --"
+)
+
+# Test: SCRIPTURA_CAT is used when set
+@test "SCRIPTURA_CAT is used when set" "$(
+    set --global --export SCRIPTURA_ROOT $test_root
+    set --global --export SCRIPTURA_CAT "head -n 1"
+    printf "line1\nline2\nline3" > "$test_root/cat_custom_test"
+    scriptura --cat cat_custom_test
+)" = line1
+
+# Test: SD_CAT is used as fallback for SCRIPTURA_CAT
+@test "SD_CAT is used as fallback for SCRIPTURA_CAT" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    set --erase SCRIPTURA_CAT
+    set --global --export SD_CAT "head -n 1"
+    printf "line1\nline2\nline3" > "$test_root/sd_cat_test"
+    scriptura --cat sd_cat_test
+) = line1
+
+# Test: unknown target shows error
+@test "unknown target shows error" -n "$(
+    set --global --export SCRIPTURA_ROOT $test_root
+    scriptura nonexistent_target 2>&1 | string match --regex "don't know what to do"
+)"
+
+# Test: help for directory without help file shows default
+@test "help for directory without help file shows default" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    mkdir -p "$test_root/no_help_dir"
+    scriptura --help no_help_dir
+) = "no_help_dir commands"
+
+# Test: shebang lines are excluded from description
+@test "shebang lines are excluded from description" (
+    set --global --export SCRIPTURA_ROOT $test_root
+    printf "#!/usr/bin/env fish\n#! Not a shebang\n# Real description\n" > "$test_root/shebang_desc_test"
+    chmod +x "$test_root/shebang_desc_test"
+    scriptura --help shebang_desc_test
+) = "Real description"
+
+# Cleanup
+cleanup