name: "Parameter expansion"
cases:
  - name: "String length"
    stdin: |
      x="abc"
      echo "len = ${#x}"

  - name: "Parameter expression: default value"
    stdin: |
      value="value"
      empty=""
      declare declared
      unset undeclared

      # -
      echo "\${value-default}       : ${value-default}"
      echo "\${empty-default}       : ${empty-default}"
      echo "\${declared-default}    : ${declared-default}"
      echo "\${undeclared-default}  : ${undeclared-default}"

      echo "\${value-}              : ${value-}"
      echo "\${empty-}              : ${empty-}"
      echo "\${declared-}           : ${declared-}"
      echo "\${undeclared-}         : ${undeclared-}"

      # :-
      echo "\${value:-default}      : ${value:-default}"
      echo "\${empty:-default}      : ${empty:-default}"
      echo "\${declared:-default}   : ${declared:-default}"
      echo "\${undeclared:-default} : ${undeclared:-default}"

      echo "\${value:-}             : ${value:-}"
      echo "\${empty:-}             : ${empty:-}"
      echo "\${declared:-}          : ${declared:-}"
      echo "\${undeclared:-}        : ${undeclared:-}"

  - name: "Parameter expression: assign default value (no colon)"
    stdin: |
      value="value"
      empty=""
      declare declared
      unset undeclared

      # =
      echo "\${value=default}       : ${value=default}"
      declare -p value
      echo "\${empty=default}       : ${empty=default}"
      declare -p empty
      echo "\${declared=default}    : ${declared=default}"
      declare -p declared
      echo "\${undeclared=default}  : ${undeclared=default}"
      declare -p undeclared

  - name: "Parameter expression: assign default value (no colon, empty replacement)"
    stdin: |
      value="value"
      empty=""
      declare declared
      unset undeclared

      # =
      echo "\${value=}              : ${value=}"
      declare -p value
      echo "\${empty=}              : ${empty=}"
      declare -p empty
      echo "\${declared=}           : ${declared=}"
      declare -p declared
      echo "\${undeclared=}         : ${undeclared=}"
      declare -p undeclared

  - name: "Parameter expression: assign default value (colon)"
    stdin: |
      value="value"
      empty=""
      declare declared
      unset undeclared

      # :=
      echo "\${value:=default}       : ${value:=default}"
      declare -p value
      echo "\${empty:=default}       : ${empty:=default}"
      declare -p empty
      echo "\${declared:=default}    : ${declared:=default}"
      declare -p declared
      echo "\${undeclared:=default}  : ${undeclared:=default}"
      declare -p undeclared

  - name: "Parameter expression: assign default value (colon, empty replacement)"
    stdin: |
      value="value"
      empty=""
      declare declared
      unset undeclared

      # :=
      echo "\${value:=}              : ${value:=}"
      declare -p value
      echo "\${empty:=}              : ${empty:=}"
      declare -p empty
      echo "\${declared:=}           : ${declared:=}"
      declare -p declared
      echo "\${undeclared:=}         : ${undeclared:=}"
      declare -p undeclared

  - name: "Parameter expression: alternative value"
    stdin: |
      value="value"
      empty=""
      declare declared
      unset undeclared

      # +
      echo "\${value+default}       : ${value+default}"
      echo "\${empty+default}       : ${empty+default}"
      echo "\${declared+default}    : ${declared+default}"
      echo "\${undeclared+default}  : ${undeclared+default}"

      echo "\${value+}              : ${value+}"
      echo "\${empty+}              : ${empty+}"
      echo "\${declared+}           : ${declared+}"
      echo "\${undeclared+}         : ${undeclared+}"

      # :+
      echo "\${value:+default}      : ${value:+default}"
      echo "\${empty:+default}      : ${empty:+default}"
      echo "\${declared:+default}   : ${declared:+default}"
      echo "\${undeclared:+default} : ${undeclared:+default}"

      echo "\${value:+}             : ${value:+}"
      echo "\${empty:+}             : ${empty:+}"
      echo "\${declared:+}          : ${declared:+}"
      echo "\${undeclared:+}        : ${undeclared:+}"

  - name: "Parameter expression: advanced alternative value"
    stdin: |
      value="value"

      echo ${value:+\x}
      echo ${value:+'x'}
      echo "${value:+\x}"
      echo "${value:+'x'}"
      echo "${value:+x y}"
      echo "${value:+z 'x' 'y' w}"
      echo "${value:+x'y'x}"
      echo "${value:+"x y"}"
      echo "${value:+"x\xy"}"
      echo "${value:+z"x\xy"z}"

  - name: "Parameter expression: error on condition (interactive)"
    ignore_stderr: true
    args: ["-i"]
    stdin: |
      value="value"
      empty=""
      declare declared
      unset undeclared

      # ?
      echo "\${value?error message}       : ${value?error message}"
      echo "  -> result: $?"
      echo "\${empty?error message}       : ${empty?error message}"
      echo "  -> result: $?"
      echo "\${declared?error message}    : ${declared?error message}"
      echo "  -> result: $?"
      echo "\${undeclared?error message}  : ${undeclared?error message}"
      echo "  -> result: $?"

      echo "\${value?}                    : ${value?}"
      echo "  -> result: $?"
      echo "\${empty?}                    : ${empty?}"
      echo "  -> result: $?"
      echo "\${declared?}                 : ${declared?}"
      echo "  -> result: $?"
      echo "\${undeclared?}               : ${undeclared?}"
      echo "  -> result: $?"

      # :?
      echo "\${value:?error message}      : ${value:?error message}"
      echo "  -> result: $?"
      echo "\${empty:?error message}      : ${empty:?error message}"
      echo "  -> result: $?"
      echo "\${declared:?error message}   : ${declared:?error message}"
      echo "  -> result: $?"
      echo "\${undeclared:?error message} : ${undeclared:?error message}"
      echo "  -> result: $?"

      echo "\${value:?}                   : ${value:?}"
      echo "  -> result: $?"
      echo "\${empty:?}                   : ${empty:?}"
      echo "  -> result: $?"
      echo "\${declared:?}                : ${declared:?}"
      echo "  -> result: $?"
      echo "\${undeclared:?}              : ${undeclared:?}"
      echo "  -> result: $?"

  - name: "Parameter expression: error on condition (non-interactive)"
    ignore_stderr: true
    stdin: |
      echo "${non_existent_var?error message}"
      echo "This should never execute"

  - name: "Parameter expression: expanded array as alternate value"
    stdin: |
      declare -a var=("abc" "def" "ghi" "")

      for item in "${var[@]}"; do
        echo "Item: '${item}'"
      done

      echo "Expression 1: '${var+"${var[@]}"}'"
      for item in "${var+"${var[@]}"}"; do
        echo "  -> '${item}'"
      done

      echo "Expression 2: '${var+${var[@]}}'"
      for item in "${var+${var[@]}}"; do
        echo "  -> '${item}'"
      done

      echo "Expression 3: '${var+"${var[@]}"}'"
      for item in ${var+"${var[@]}"}; do
        echo "  -> '${item}'"
      done

      echo "Expression 4: '${var+${var[@]}}'"
      for item in ${var+${var[@]}}; do
        echo "  -> '${item}'"
      done

      echo "Expression 5: '${var+"${var[*]}"}'"
      for item in "${var+"${var[*]}"}"; do
        echo "  -> '${item}'"
      done

      echo "Expression 6: '${var+${var[*]}}'"
      for item in "${var+${var[*]}}"; do
        echo "  -> '${item}'"
      done

      echo "Expression 7: '${var+"${var[*]}"}'"
      for item in ${var+"${var[*]}"}; do
        echo "  -> '${item}'"
      done

      echo "Expression 8: '${var+${var[*]}}'"
      for item in ${var+${var[*]}}; do
        echo "  -> '${item}'"
      done

  - name: "Parameter expression: expanded array as default value"
    stdin: |
      declare -a var=("abc" "def" "ghi" "")

      for item in "${var[@]}"; do
        echo "Item: '${item}'"
      done

      echo "Expression 1: ${nonexistent-${var[@]}}"
      for item in ${nonexistent-${var[@]}}; do
        echo "  -> '${item}'"
      done

      echo "Expression 2: ${nonexistent-"${var[@]}"}"
      for item in ${nonexistent-"${var[@]}"}; do
        echo "  -> '${item}'"
      done

      echo "Expression 3: ${nonexistent2=${var[@]}}"
      for item in ${nonexistent3=${var[@]}}; do
        echo "  -> '${item}'"
      done

      echo "Expression 4: ${nonexistent4="${var[@]}"}"
      for item in ${nonexistent5-"${var[@]}"}; do
        echo "  -> '${item}'"
      done

  - name: "Remove prefix/suffix"
    stdin: |
      var="prepre-abc-sufsuf"

      # Smallest suffix
      shopt -u nocasematch
      echo "\${var%}:    ${var%}"
      echo "\${var%pre}: ${var%pre}"
      echo "\${var%suf}: ${var%suf}"
      echo "\${var%SUF}: ${var%SUF}"
      shopt -s nocasematch
      echo "\${var%SUF}(nocasematch): ${var%SUF}"

      # Largest suffix
      shopt -u nocasematch
      echo "\${var%%}:    ${var%%}"
      echo "\${var%%pre}: ${var%%pre}"
      echo "\${var%%suf}: ${var%%suf}"
      echo "\${var%%SUF}: ${var%%SUF}"
      shopt -s nocasematch
      echo "\${var%%SUF}(nocasematch): ${var%%SUF}"

      # Smallest prefix
      shopt -u nocasematch
      echo "\${var#}:     ${var#}"
      echo "\${var#pre}:  ${var#pre}"
      echo "\${var#suf}:  ${var#suf}"
      echo "\${var#PRE}:  ${var#PRE}"
      shopt -s nocasematch
      echo "\${var#PRE}(nocasematch):  ${var#PRE}"

      # Largest prefix
      shopt -u nocasematch
      echo "\${var##}:    ${var##}"
      echo "\${var##pre}: ${var##pre}"
      echo "\${var##suf}: ${var##suf}"
      echo "\${var##PRE}: ${var##PRE}"
      shopt -s nocasematch
      echo "\${var##PRE}(nocasematch): ${var##PRE}"

  - name: "Indirect variable references"
    stdin: |
      var="Hello"
      ref="var"
      echo "${!ref}"
      echo "${!ref//l/o}"

  - name: "Indirect variable references with special parameters"
    stdin: |
      set a b c

      ref="2"
      echo "${!ref}"

  - name: "Indirect variable references with array"
    stdin: |
      arr=("element1" "element2" "element3")

      ref="arr[1]"
      echo "${!ref}"

      ref="arr[10]"
      echo "${!ref}"

  - name: "Variable prefix match"
    stdin: |
      var1="Hello"
      var2="World"

      echo "${!var*}"
      echo "${!var@}"

      echo "Dumping *"
      for i in "${!var*}"; do
          echo "i: $i"
      done

      echo "Dumping @"
      for i in "${!var@}"; do
          echo "i: $i"
      done

  - name: "Uppercase first character"
    stdin: |
      var="hello"

      shopt -u nocasematch
      echo "\${var^}:   ${var^}"
      echo "\${var^h}:  ${var^h}"
      echo "\${var^H}:  ${var^H}"
      echo "\${var^l}:  ${var^l}"
      echo "\${var^h*}: ${var^h*}"
      echo "\${var^he}: ${var^he}"
      echo "\${var^?}:  ${var^?}"
      echo "\${var^*}:  ${var^*}"

      shopt -s nocasematch
      echo "\${var^H}(nocasematch): ${var^H}"

      arr=("hello" "world")
      echo "\${arr^}: ${arr^}"
      echo "\${arr[@]^}: ${arr[@]^}"
      echo "\${arr[*]^}: ${arr[*]^}"

  - name: "Uppercase matching pattern"
    stdin: |
      var="hello"

      shopt -u nocasematch
      echo "\${var^^}:  ${var^^}"
      echo "\${var^^l}: ${var^^l}"
      echo "\${var^^L}: ${var^^L}"
      echo "\${var^^m}: ${var^^m}"

      shopt -s nocasematch
      echo "\${var^^L}(nocasematch): ${var^^L}"

      arr=("hello" "world")
      echo "\${arr^^}: ${arr^^}"
      echo "\${arr[@]^^}: ${arr[@]^^}"
      echo "\${arr[*]^^}: ${arr[*]^^}"

  - name: "Lowercase first character"
    stdin: |
      var="HELLO"

      shopt -u nocasematch
      echo "\${var,}:   ${var,}"
      echo "\${var,h}:  ${var,h}"
      echo "\${var,H}:  ${var,H}"
      echo "\${var,L}:  ${var,L}"
      echo "\${var,H*}: ${var,H*}"
      echo "\${var,HE}: ${var,HE}"
      echo "\${var,?}:  ${var,?}"
      echo "\${var,*}:  ${var,*}"

      shopt -s nocasematch
      echo "\${var,h}(nocasematch):  ${var,h}"

      arr=("HELLO" "WORLD")
      echo "\${arr,}: ${arr,}"
      echo "\${arr[@],}: ${arr[@],}"
      echo "\${arr[*],}: ${arr[*],}"

  - name: "Lowercase matching pattern"
    stdin: |
      var="HELLO"

      shopt -u nocasematch
      echo "\${var,,}:  ${var,,}"
      echo "\${var,,M}: ${var,,M}"
      echo "\${var,,L}: ${var,,L}"
      echo "\${var,,l}: ${var,,l}"

      shopt -s nocasematch
      echo "\${var,,l}(nocasematch): ${var,,l}"

      arr=("HELLO" "WORLD")
      echo "\${arr,,}: ${arr,,}"
      echo "\${arr[@],,}: ${arr[@],,}"
      echo "\${arr[*],,}: ${arr[*],,}"

  - name: "Substring replacement"
    stdin: |
      var="Hello, world!"
      echo "\${var/world/WORLD}: ${var/world/WORLD}"

      arr=("world" "world")
      echo "\${arr/world/WORLD}: ${arr/world/WORLD}"
      echo "\${arr[@]/world/WORLD}: ${arr[@]/world/WORLD}"
      echo "\${arr[*]/world/WORLD}: ${arr[*]/world/WORLD}"

  - name: "Substring replacement with slashes"
    stdin: |
      var="Hello, world!"
      echo "\${var/world//world}: ${var/world//world}"

  - name: "Substring replacement with patterns"
    stdin: |
      var="a[bc]d"
      pattern="[bc]"
      echo "Replacement 1: ${var/${pattern}/}"
      echo "Replacement 2: ${var/"${pattern}"/}"

  - name: "Prefix substring replacement"
    stdin: |
      var="Hello, world!"
      echo "\${var/#world/WORLD}: ${var/#world/WORLD}"
      echo "\${var/#Hello/HELLO}: ${var/#Hello/HELLO}"

      arr=("world" "world")
      echo "\${arr/#world/WORLD}: ${arr/#world/WORLD}"
      echo "\${arr[@]/#world/WORLD}: ${arr[@]/#world/WORLD}"
      echo "\${arr[*]/#world/WORLD}: ${arr[*]/#world/WORLD}"

  - name: "Suffix substring replacement"
    stdin: |
      var="Hello, world!"
      echo "\${var/%Hello/HELLO}:   ${var/%Hello/HELLO}"
      echo "\${var/%world!/WORLD!}: ${var/%world!/WORLD!}"

      arr=("world" "world")
      echo "\${arr/%world/WORLD}: ${arr/%world/WORLD}"
      echo "\${arr[@]/%world/WORLD}: ${arr[@]/%world/WORLD}"
      echo "\${arr[*]/%world/WORLD}: ${arr[*]/%world/WORLD}"

  - name: "Global substring replacement"
    stdin: |
      var="Hello, world, world!"
      echo "\${var//world/WORLD}: ${var//world/WORLD}"

      arr=("world world" "world world")
      echo "\${arr//world/WORLD}: ${arr//world/WORLD}"
      echo "\${arr[@]//world/WORLD}: ${arr[@]//world/WORLD}"
      echo "\${arr[*]//world/WORLD}: ${arr[*]//world/WORLD}"

  - name: "Global substring removal"
    stdin: |
      var="That is not all"

      shopt -u nocasematch
      echo "\${var//not }: ${var//not}"

      shopt -s nocasematch
      echo "\${var//NOT }: ${var//NOT }"

  - name: "Substring from offset"
    stdin: |
      var="Hello, world!"
      echo "\${var:0}:   ${var:0}"
      echo "\${var:7}:   ${var:7}"
      echo "\${var: 7 }: ${var: 7 }"
      echo "\${var:50}:  ${var:50}"
      echo "\${var:-1}:  ${var:-1}"
      echo "\${var: -1}: ${var: -1}"
      echo "\${var: 2 + 3 }: ${var: 2 + 3 }"

  - name: "Substring with length"
    stdin: |
      var="Hello, world!"
      echo "\${var:0:1}:  ${var:0:1}"
      echo "\${var:0:0}:  ${var:0:0}"
      echo "\${var:0:50}: ${var:0:50}"
      echo "\${var:0:-1}: ${var:0:-1}"
      echo "\${var:0:-3}: ${var:0:-3}"
      echo "\${var:7:3}:  ${var:7:3}"
      echo "\${var:50:2}: ${var:50:2}"
      echo "\${var:-1:1}: ${var:-1:1}"
      echo "\${var:-3:1}: ${var:-3:1}"

  - name: "Substring on string with multi-byte chars"
    skip: true # TODO(expansion): succeeds on macOS, fails on Linux
    stdin: |
      var="7❌🖌️✅😂🔴⛔ABC"
      echo "${var:2}" | hexdump -C

  - name: "Substring operator on arrays"
    stdin: |
      set abcde fghij klmno pqrst uvwxy z
      echo "\${@:2:2}: ${@:2:2}"
      echo "\${@:2}: ${@:2}"

      myarray=(abcde fghij klmno pqrst uvwxy z)
      echo "\${myarray[@]:2:2}: ${myarray[@]:2:2}"
      echo "\${myarray[@]:2}: ${myarray[@]:2}"

  - name: "Substring operator on arrays with negative index"
    stdin: |
      set abcde fghij klmno pqrst uvwxy z
      echo "\${@: -2:2}: ${@: -2:2}"
      echo "\${@: -2}: ${@: -2}"

      myarray=(abcde fghij klmno pqrst uvwxy z)
      echo "\${myarray[@]: -2:2}: ${myarray[@]: -2:2}"
      echo "\${myarray[@]: -2}: ${myarray[@]: -2}"

  - name: "Substring operator on single-element array"
    stdin: |
      myarray=("abcde fghij klmno pqrst uvwxy z")
      echo "\${myarray[@]:0:1}: ${myarray[@]:0:1}"
      echo "\${myarray[@]:1}: ${myarray[@]:1}"

  - name: "Substring operator past end of array"
    stdin: |
      set a b c
      declare -a result1=("${@:3}")
      declare -p result1

      myarray=(a b c)
      declare -a result2=("${myarray[@]:3}")
      declare -p result2

  - name: "Substring with length (with nested expressions)"
    stdin: |
      var="Hello, world!"
      offset=7
      length=5
      echo "\${var:\$offset:\${length}}: ${var:$offset:${length}}"