const SPACING = Dict(
    "Issue #142 italic roman boundaries" => [
        raw"f(t)",
        raw"g(x)",
        raw"(f)x",
        raw"(t)",
        raw"\eta(t)",
        raw"\alpha(t)",
        raw"W(\alpha,\alpha^*)",
        raw"g(f(x))",
        raw"\mathrm{y}(x)",
        raw"\mathrm{g}t",
    ],
    "Issue #95 lower-case Greek and subscript spacing" => [
        raw"\eta(t)",
        raw"\alpha_k",
        raw"\omega_k",
        raw"k\xi",
        raw"\nu(k)",
        raw"N_\nu L_\nu A_\nu J_\nu",
        raw"x_{\alpha(k)}",
        raw"v_{(a + b)_k}^i",
        raw"\partial_i u_j",
        raw"\phi_\varphi \rho_\sigma",
    ],
    "Subscript and superscript combinations" => [
        raw"x_i",
        raw"x^i",
        raw"x_i^j",
        raw"V^i_j",
        raw"x_{i_j}",
        raw"x^{i^j}",
        raw"x_{(a+b)_k}^i",
        raw"T_{\alpha\beta}^{ij}",
        raw"\Gamma^\mu_{\nu\rho}",
        raw"\psi^\dagger_i\psi_i",
    ],
    "PR #151 primes and deep scripts" => [
        raw"x' f'",
        raw"x'' f''",
        raw"x′ f′",
        raw"x\prime f\prime",
        raw"x^\prime f^\prime",
        raw"x'_y f_g'",
        raw"A^{B^{C^{D^E}}}_{F_{G_{H_I}}}",
        raw"f^{A'}",
    ],
    "Roman upright and capital boundaries" => [
        raw"\mathrm{d}x",
        raw"\mathrm{e}^{-x}",
        raw"\mathrm{Re}\,z",
        raw"\mathrm{Im}\,z",
        raw"\mathrm{Tr}\,A_i^j",
        raw"\mathrm{Cov}(X,Y)",
        raw"A_\nu B_\nu C_\nu D_\nu",
        raw"M\mathrm{M}M",
    ],
    "Issue #129 math operator spacing" => [
        raw"\log x",
        raw"\log(x)",
        raw"\sin x",
        raw"\sin(x)",
        raw"\exp t",
        raw"\exp(t)",
        raw"\max_{t \in \{1,...,5\}}",
    ],
    "Operators, delimiters, and fractions" => [
        raw"-1,\ 2-1,\ (-1)",
        raw"\alpha^*",
        raw"\psi^* \psi",
        raw"\frac{1}{2}\pm\sqrt{3}",
        raw"\frac{1}{2}{}\pm\sqrt{3}",
        raw"\left(\frac{1}{2}\right)f(t)",
        raw"\sqrt{x_i^2+y_i^2}",
        raw"\sum_{k=0}^n a_k x^k",
        raw"\int_0^{2\pi}\sin(x)\,dx",
    ],
    "Script layout issues #93, #105, #110, #126" => [
        raw"\left(\frac{dy}{dx}\right)_0",
        raw"\left(\frac{A^{xy}}{B}\right)^{1/4}",
        raw"(\frac{A^{xy}}{B})^{1/4}",
        raw"\left\langle\left|\int\right|\right\rangle",
        raw"\left\langle\left|\left\langle\left|\int\right|\right\rangle\right|\right\rangle",
        raw"x^{\frac{1}{1+2}}",
        raw"x_{\frac{1}{1+2}}",
    ],
    "Nested expressions" => [
        raw"\frac{\alpha_i+\beta_i}{\gamma_i+\delta_i}",
        raw"\sqrt{\frac{1+\alpha_k}{1+\beta_k}}",
        raw"F_{\mu\nu}F^{\mu\nu}",
        raw"\overline{z}_i",
        raw"\left(\alpha_{(i+j)_k}\right)^2",
        raw"\frac{\partial^2 f}{\partial x_i\partial x_j}",
    ],
)
