rxTest({
  f <- function() {
    ini({
      tke <- 0.5
      eta.ke ~ 0.04
      prop.sd <- sqrt(0.1)
    })
    model({
      ke <- tke * exp(eta.ke)
      ipre <- 10 * exp(-ke * t)
      f2 <- ipre / (ipre + 5)
      f3 <- f2 * 3
      lipre <- log(ipre)
      ipre ~ prop(prop.sd)
    })
  }

  expect_equal_quietly <- function(ui, expected) {
    uiUp <- suppressMessages(force(ui))
    expect_equal(.rxGetVarianceForErrorType(uiUp, uiUp$predDf[1, ]), expected)
  }

  test_that("constant error model tests", {
    # Constant:  y=f+a*err
    # Var = a^2

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd)),
      quote((add.sd) ^ 2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2)),
      quote((f2) ^ 2)
    )
  })

  test_that("prop model tests", {
    # Proportional:  y=f+b*f*err
    # Var = (f*b)^2

    expect_equal_quietly(
      f %>% model(ipre ~ prop(prop.sd)),
      quote((rx_pred_f_ * prop.sd) ^ 2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ prop(f2)),
      quote((rx_pred_f_ * f2) ^ 2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ propT(prop.sd)),
      quote((rx_pred_ * prop.sd) ^ 2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ propT(f2)),
      quote((rx_pred_ * f2) ^ 2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ propF(prop.sd, f3)),
      quote((f3 * prop.sd) ^ 2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ propF(f2, f3)),
      quote((f3 * f2) ^ 2)
    )
  })

  test_that("power models", {
    # Power:  y=f+b*f^c*err
    # Var = (f^c*b)^2

    # pow(sd,pw)
    expect_equal_quietly(
      f %>% model(ipre ~ pow(prop.sd, pw)),
      quote(((rx_pred_f_)^(pw) * prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ pow(f2, pw)),
      quote(((rx_pred_f_)^(pw) * f2)^2)
    )

    # powT(sd,pw)
    expect_equal_quietly(
      f %>% model(ipre ~ powT(prop.sd, pw)),
      quote(((rx_pred_)^(pw) * prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ powT(f2, pw)),
      quote(((rx_pred_)^(pw) * f2)^2)
    )

    # powF(sd,pw,f)
    expect_equal_quietly(
      f %>% model(ipre ~ powF(prop.sd, pw, f3)),
      quote(((f3)^(pw) * prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ powF(f2, pw, f3)),
      quote(((f3)^(pw) * f2)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ powF(f2, lipre, f3)),
      quote(((f3)^(lipre) * f2)^2)
    )
  })

  test_that("add+prop combined1", {
    # Combined1:  y=f + (a+b*f^c)*err
    # Var = (a + b*f^c)^2

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + prop(prop.sd) + combined1()),
      quote(((add.sd) + (rx_pred_f_) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>%
        model(ipre ~ add(f2) + prop(prop.sd) + combined1()),
      quote(((f2) + (rx_pred_f_) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + prop(f2) + combined1()),
      quote(((add.sd) + (rx_pred_f_) * (f2))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + prop(f3) + combined1()),
      quote(((f2) + (rx_pred_f_) * (f3))^2)
    )

    # propT
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propT(prop.sd) + combined1()),
      quote(((add.sd) + (rx_pred_) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + propT(prop.sd) + combined1()),
      quote(((f2) + (rx_pred_) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propT(f2) + combined1()),
      quote(((add.sd) + (rx_pred_) * (f2))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + propT(f3) + combined1()),
      quote(((f2) + (rx_pred_) * (f3))^2)
    )

    # propF
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propF(prop.sd, f3) + combined1()),
      quote(((add.sd) + (f3) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + propF(prop.sd, f3) + combined1()),
      quote(((lipre) + (f3) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propF(lipre, f3) + combined1()),
      quote(((add.sd) + (f3) * (lipre))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + propF(f2, f3) + combined1()),
      quote(((lipre) + (f3) * (f2))^2)
    )
  })

  test_that("add+pow combined1", {
    # Combined1:  y=f + (a+b*f^c)*err
    # Var = (a + b*f^c)^2

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + pow(prop.sd, c) + combined1()),
      quote(((add.sd) + (rx_pred_f_) ^ (c) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>%
        model(ipre ~ add(f2) + pow(prop.sd, c) + combined1()),
      quote(((f2) + (rx_pred_f_) ^ (c) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + pow(f2, c) + combined1()),
      quote(((add.sd) + (rx_pred_f_) ^ (c)* (f2))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + pow(f3, c) + combined1()),
      quote(((f2) + (rx_pred_f_) ^ (c) * (f3))^2)
    )

    # propT
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powT(prop.sd, c) + combined1()),
      quote(((add.sd) + (rx_pred_) ^ (c) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + powT(prop.sd, c) + combined1()),
      quote(((f2) + (rx_pred_) ^ (c)* (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powT(f2, c) + combined1()),
      quote(((add.sd) + (rx_pred_) ^ (c)* (f2))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + powT(f3, c) + combined1()),
      quote(((f2) + (rx_pred_) ^ (c) * (f3))^2)
    )

    # propF
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powF(prop.sd, c, f3) + combined1()),
      quote(((add.sd) + (f3) ^ (c) * (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + powF(prop.sd, c, f3) + combined1()),
      quote(((lipre) + (f3) ^ (c)* (prop.sd))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powF(lipre, c, f3) + combined1()),
      quote(((add.sd) + (f3) ^ (c) * (lipre))^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + powF(f2, c, f3) + combined1()),
      quote(((lipre) + (f3) ^ (c)* (f2))^2)
    )
  })

  # combined2
  test_that("add+prop combined2", {
    # Combined2:  y=f + sqrt(a^2 + b^2*(f^c)^2)*err
    # Var = a^2 + b^2*(f^c)^2

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + prop(prop.sd) + combined2()),
      quote((add.sd)^2 + (rx_pred_f_)^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + prop(prop.sd) + combined2()),
      quote((f2)^2 + (rx_pred_f_)^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + prop(f2) + combined2()),
      quote((add.sd)^2 + (rx_pred_f_)^2 * (f2)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + prop(f3) + combined2()),
      quote((f2)^2 + (rx_pred_f_)^2 * (f3)^2)
    )

    # propT
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propT(prop.sd) + combined2()),
      quote((add.sd)^2 + (rx_pred_)^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + propT(prop.sd) + combined2()),
      quote((f2)^2 + (rx_pred_)^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propT(f2) + combined2()),
      quote((add.sd)^2 + (rx_pred_)^2 * (f2)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + propT(f3) + combined2()),
      quote((f2)^2 + (rx_pred_)^2 * (f3)^2)
    )

    # propF
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propF(prop.sd, f3) + combined2()),
      quote((add.sd)^2 + (f3)^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + propF(prop.sd, f3) + combined2()),
      quote((lipre)^2 + (f3)^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + propF(lipre, f3) + combined2()),
      quote((add.sd)^2 + (f3)^2 * (lipre)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + propF(f2, f3) + combined2()),
      quote((lipre)^2 + (f3)^2 * (f2)^2)
    )
  })


  test_that("add+pow combined2", {
    # Combined2:  y=f + (a+b*f^c)*err
    # Var = (a + b*f^c)^2

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + pow(prop.sd, c) + combined2()),
      quote((add.sd)^2 + ((rx_pred_f_)^(c))^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + pow(prop.sd, c) + combined2()),
      quote((f2)^2 + ((rx_pred_f_)^(c))^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + pow(f2, c) + combined2()),
      quote((add.sd)^2 + ((rx_pred_f_)^(c))^2 * (f2)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + pow(f3, c) + combined2()),
      quote((f2)^2 + ((rx_pred_f_)^(c))^2 * (f3)^2)
    )

    # propT
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powT(prop.sd, c) + combined2()),
      quote((add.sd)^2 + ((rx_pred_)^(c))^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + powT(prop.sd, c) + combined2()),
      quote((f2)^2 + ((rx_pred_)^(c))^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powT(f2, c) + combined2()),
      quote((add.sd)^2 + ((rx_pred_)^(c))^2 * (f2)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(f2) + powT(f3, c) + combined2()),
      quote((f2)^2 + ((rx_pred_)^(c))^2 * (f3)^2)
    )

    # propF
    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powF(prop.sd, c, f3) + combined2()),
      quote((add.sd)^2 + ((f3)^(c))^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + powF(prop.sd, c, f3) + combined2()),
      quote((lipre)^2 + ((f3)^(c))^2 * (prop.sd)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(add.sd) + powF(lipre, c, f3) + combined2()),
      quote((add.sd)^2 + ((f3)^(c))^2 * (lipre)^2)
    )

    expect_equal_quietly(
      f %>% model(ipre ~ add(lipre) + powF(f2, c, f3) + combined2()),
      quote((lipre)^2 + ((f3)^(c))^2 * (f2)^2)
    )
  })
})